Reply
Page 1 of 3 1 2 3 LastLast
Results 1 to 30 of 63
  1. #1
    Old School Lunatic's Avatar
    Join Date: Feb 2106
    Location: United States
    Stats: 2'7", 205 lbs
    Posts: 47,421
    BodyPoints: 36180
    Rep Power: 246367
    Lunatic has a reputation beyond repute. Second best rank possible! (+100000) Lunatic has a reputation beyond repute. Second best rank possible! (+100000) Lunatic has a reputation beyond repute. Second best rank possible! (+100000) Lunatic has a reputation beyond repute. Second best rank possible! (+100000) Lunatic has a reputation beyond repute. Second best rank possible! (+100000) Lunatic has a reputation beyond repute. Second best rank possible! (+100000) Lunatic has a reputation beyond repute. Second best rank possible! (+100000) Lunatic has a reputation beyond repute. Second best rank possible! (+100000) Lunatic has a reputation beyond repute. Second best rank possible! (+100000) Lunatic has a reputation beyond repute. Second best rank possible! (+100000) Lunatic has a reputation beyond repute. Second best rank possible! (+100000)
    Lunatic is offline

    Need Physics Help(5 problems)[will rep]

    Don't care about the work being showed right now. I just need answers by 11:59 The fifth question is attached and includes a picture. Will rep for correct answers.




    2. How much work is done by the motor in a CD player to make a CD spin, starting from rest? The CD has a diameter of 12.2 cm and a mass of 15.6 g. The laser scans at a constant tangential velocity of 1.14 m/s. Assume that the music is first detected at a radius of 19.8 mm from the center of the disk. Ignore the small circular hole at the CD's center.

    5. A playground merry-go-round made in the shape of a solid disk, has a diameter of 2.64 m and a mass of 350.1 kg. Two children, each of mass 30.0 kg, sit on opposite sides at the edge of the platform. Approximate the children as point masses.

    (a) What torque is required to bring the merry-go-round from rest to 29 rpm in 19.5 s?

    (b) If two other bigger children are going to push on the merry-go-round rim to produce this acceleration, with what force magnitude must each child push?


    6. A solid sphere of mass 0.604 kg rolls without slipping along a horizontal surface with a translational speed of 5.28 m/s. It comes to an incline that makes an angle of 38? with the horizontal surface. Neglect energy losses due to friction.

    (a) What is the total energy of the rolling sphere?

    (b) To what vertical height above the horizontal surface does the sphere rise on the incline?


    9. A uniform disk with a mass of 815 g and radius 17.0 cm is rotating on frictionless bearings with an rotational speed of 18.0 Hz when Jill drops a 105 g clod of clay on a point 7.50 cm from the center of the disk, where it sticks. What is the new rotational speed of the disk?
    Attached Images
    Last edited by Lunatic; 11-02-2009 at 09:06 PM.
    || LSU Tigers || New Orleans Saints || Washington Nationals || LOL at basketball ||

    Mechanical Engineer in training

    “We are all born ignorant, but one must work hard to remain stupid.”
    ― Benjamin Franklin

    "Real knowledge is to know the extent of one’s ignorance."
    ― Confucius

    "The realization of ignorance is the first act of knowing."
    ― Jean Toomer
    Reply With Quote

  2. #2
    my job title is douchebag Iukas's Avatar
    Join Date: Jun 2009
    Location: United States
    Age: 25
    Stats: 6'1", 181 lbs
    Posts: 10,665
    Rep Power: 13187
    Iukas is a splendid one to behold. (+10000) Iukas is a splendid one to behold. (+10000) Iukas is a splendid one to behold. (+10000) Iukas is a splendid one to behold. (+10000) Iukas is a splendid one to behold. (+10000) Iukas is a splendid one to behold. (+10000) Iukas is a splendid one to behold. (+10000) Iukas is a splendid one to behold. (+10000) Iukas is a splendid one to behold. (+10000) Iukas is a splendid one to behold. (+10000) Iukas is a splendid one to behold. (+10000)
    Iukas is offline
    1st
    by the way i do not know physics at all, just wanted to be first.
    Reply With Quote

  3. #3
    Old School Lunatic's Avatar
    Join Date: Feb 2106
    Location: United States
    Stats: 2'7", 205 lbs
    Posts: 47,421
    BodyPoints: 36180
    Rep Power: 246367
    Lunatic has a reputation beyond repute. Second best rank possible! (+100000) Lunatic has a reputation beyond repute. Second best rank possible! (+100000) Lunatic has a reputation beyond repute. Second best rank possible! (+100000) Lunatic has a reputation beyond repute. Second best rank possible! (+100000) Lunatic has a reputation beyond repute. Second best rank possible! (+100000) Lunatic has a reputation beyond repute. Second best rank possible! (+100000) Lunatic has a reputation beyond repute. Second best rank possible! (+100000) Lunatic has a reputation beyond repute. Second best rank possible! (+100000) Lunatic has a reputation beyond repute. Second best rank possible! (+100000) Lunatic has a reputation beyond repute. Second best rank possible! (+100000) Lunatic has a reputation beyond repute. Second best rank possible! (+100000)
    Lunatic is offline
    Originally Posted by Iukas View Post
    1st
    by the way i do not know physics at all, just wanted to be first.
    Gay
    || LSU Tigers || New Orleans Saints || Washington Nationals || LOL at basketball ||

    Mechanical Engineer in training

    “We are all born ignorant, but one must work hard to remain stupid.”
    ― Benjamin Franklin

    "Real knowledge is to know the extent of one’s ignorance."
    ― Confucius

    "The realization of ignorance is the first act of knowing."
    ― Jean Toomer
    Reply With Quote

  4. #4
    Old School Lunatic's Avatar
    Join Date: Feb 2106
    Location: United States
    Stats: 2'7", 205 lbs
    Posts: 47,421
    BodyPoints: 36180
    Rep Power: 246367
    Lunatic has a reputation beyond repute. Second best rank possible! (+100000) Lunatic has a reputation beyond repute. Second best rank possible! (+100000) Lunatic has a reputation beyond repute. Second best rank possible! (+100000) Lunatic has a reputation beyond repute. Second best rank possible! (+100000) Lunatic has a reputation beyond repute. Second best rank possible! (+100000) Lunatic has a reputation beyond repute. Second best rank possible! (+100000) Lunatic has a reputation beyond repute. Second best rank possible! (+100000) Lunatic has a reputation beyond repute. Second best rank possible! (+100000) Lunatic has a reputation beyond repute. Second best rank possible! (+100000) Lunatic has a reputation beyond repute. Second best rank possible! (+100000) Lunatic has a reputation beyond repute. Second best rank possible! (+100000)
    Lunatic is offline
    bump for title change
    || LSU Tigers || New Orleans Saints || Washington Nationals || LOL at basketball ||

    Mechanical Engineer in training

    “We are all born ignorant, but one must work hard to remain stupid.”
    ― Benjamin Franklin

    "Real knowledge is to know the extent of one’s ignorance."
    ― Confucius

    "The realization of ignorance is the first act of knowing."
    ― Jean Toomer
    Reply With Quote

  5. #5
    WTF IS JUICE? berserkbladex's Avatar
    Join Date: Apr 2007
    Location: United States
    Stats: 5'9"
    Posts: 1,173
    BodyPoints: 2255
    Rep Power: 3064
    berserkbladex is a glorious beacon of knowledge. (+2500) berserkbladex is a glorious beacon of knowledge. (+2500) berserkbladex is a glorious beacon of knowledge. (+2500) berserkbladex is a glorious beacon of knowledge. (+2500) berserkbladex is a glorious beacon of knowledge. (+2500) berserkbladex is a glorious beacon of knowledge. (+2500) berserkbladex is a glorious beacon of knowledge. (+2500) berserkbladex is a glorious beacon of knowledge. (+2500) berserkbladex is a glorious beacon of knowledge. (+2500) berserkbladex is a glorious beacon of knowledge. (+2500) berserkbladex is a glorious beacon of knowledge. (+2500)
    berserkbladex is offline
    Originally Posted by Lunatic View Post
    Don't care about the work being showed right now. I just need answers by 11:59 The fifth question is attached and includes a picture. Will rep for correct answers.




    2. How much work is done by the motor in a CD player to make a CD spin, starting from rest? The CD has a diameter of 12.2 cm and a mass of 15.6 g. The laser scans at a constant tangential velocity of 1.14 m/s. Assume that the music is first detected at a radius of 19.8 mm from the center of the disk. Ignore the small circular hole at the CD's center.

    5. A playground merry-go-round made in the shape of a solid disk, has a diameter of 2.64 m and a mass of 350.1 kg. Two children, each of mass 30.0 kg, sit on opposite sides at the edge of the platform. Approximate the children as point masses.

    (a) What torque is required to bring the merry-go-round from rest to 29 rpm in 19.5 s?

    (b) If two other bigger children are going to push on the merry-go-round rim to produce this acceleration, with what force magnitude must each child push?


    6. A solid sphere of mass 0.604 kg rolls without slipping along a horizontal surface with a translational speed of 5.28 m/s. It comes to an incline that makes an angle of 38? with the horizontal surface. Neglect energy losses due to friction.

    (a) What is the total energy of the rolling sphere?

    (b) To what vertical height above the horizontal surface does the sphere rise on the incline?


    9. A uniform disk with a mass of 815 g and radius 17.0 cm is rotating on frictionless bearings with an rotational speed of 18.0 Hz when Jill drops a 105 g clod of clay on a point 7.50 cm from the center of the disk, where it sticks. What is the new rotational speed of the disk?
    2. .0529550685 j


    sorry dude got a test tomorrow so thats all i had time for
    Reply With Quote

  6. #6
    Registered User LAballin24's Avatar
    Join Date: Jul 2009
    Age: 29
    Posts: 4,936
    Rep Power: 3258
    LAballin24 is a glorious beacon of knowledge. (+2500) LAballin24 is a glorious beacon of knowledge. (+2500) LAballin24 is a glorious beacon of knowledge. (+2500) LAballin24 is a glorious beacon of knowledge. (+2500) LAballin24 is a glorious beacon of knowledge. (+2500) LAballin24 is a glorious beacon of knowledge. (+2500) LAballin24 is a glorious beacon of knowledge. (+2500) LAballin24 is a glorious beacon of knowledge. (+2500) LAballin24 is a glorious beacon of knowledge. (+2500) LAballin24 is a glorious beacon of knowledge. (+2500) LAballin24 is a glorious beacon of knowledge. (+2500)
    LAballin24 is offline
    Dont remember sht from physics but here is a bump.
    Reply With Quote

  7. #7
    500 Internal Server Error jujuB's Avatar
    Join Date: Apr 2008
    Location: Georgia, United States
    Stats: 6'0", 200 lbs
    Posts: 17,544
    Rep Power: 36008
    jujuB has much to be proud of. One of the best! (+20000) jujuB has much to be proud of. One of the best! (+20000) jujuB has much to be proud of. One of the best! (+20000) jujuB has much to be proud of. One of the best! (+20000) jujuB has much to be proud of. One of the best! (+20000) jujuB has much to be proud of. One of the best! (+20000) jujuB has much to be proud of. One of the best! (+20000) jujuB has much to be proud of. One of the best! (+20000) jujuB has much to be proud of. One of the best! (+20000) jujuB has much to be proud of. One of the best! (+20000) jujuB has much to be proud of. One of the best! (+20000)
    jujuB is offline
    i have a damn physics test on friday

    brb failing it, and prof. curving it so I get a C lol
    RIP mainsqueeze530 1991-2013
    Reply With Quote

  8. #8
    Stay thirsty my friends Misc_Canuck's Avatar
    Join Date: Feb 2009
    Stats: 99999'2", 1 lbs
    Posts: 5,692
    Rep Power: 2832
    Misc_Canuck is a glorious beacon of knowledge. (+2500) Misc_Canuck is a glorious beacon of knowledge. (+2500) Misc_Canuck is a glorious beacon of knowledge. (+2500) Misc_Canuck is a glorious beacon of knowledge. (+2500) Misc_Canuck is a glorious beacon of knowledge. (+2500) Misc_Canuck is a glorious beacon of knowledge. (+2500) Misc_Canuck is a glorious beacon of knowledge. (+2500) Misc_Canuck is a glorious beacon of knowledge. (+2500) Misc_Canuck is a glorious beacon of knowledge. (+2500) Misc_Canuck is a glorious beacon of knowledge. (+2500) Misc_Canuck is a glorious beacon of knowledge. (+2500)
    Misc_Canuck is offline
    only phy 12 sawwy
    RIP Zyzz (made by me): http://zyzzhnng.ytmnd.com/
    Reply With Quote

  9. #9
    Old School Lunatic's Avatar
    Join Date: Feb 2106
    Location: United States
    Stats: 2'7", 205 lbs
    Posts: 47,421
    BodyPoints: 36180
    Rep Power: 246367
    Lunatic has a reputation beyond repute. Second best rank possible! (+100000) Lunatic has a reputation beyond repute. Second best rank possible! (+100000) Lunatic has a reputation beyond repute. Second best rank possible! (+100000) Lunatic has a reputation beyond repute. Second best rank possible! (+100000) Lunatic has a reputation beyond repute. Second best rank possible! (+100000) Lunatic has a reputation beyond repute. Second best rank possible! (+100000) Lunatic has a reputation beyond repute. Second best rank possible! (+100000) Lunatic has a reputation beyond repute. Second best rank possible! (+100000) Lunatic has a reputation beyond repute. Second best rank possible! (+100000) Lunatic has a reputation beyond repute. Second best rank possible! (+100000) Lunatic has a reputation beyond repute. Second best rank possible! (+100000)
    Lunatic is offline
    Originally Posted by berserkbladex View Post
    2. .0529550685 j


    sorry dude got a test tomorrow so thats all i had time for
    Didn't work
    || LSU Tigers || New Orleans Saints || Washington Nationals || LOL at basketball ||

    Mechanical Engineer in training

    “We are all born ignorant, but one must work hard to remain stupid.”
    ― Benjamin Franklin

    "Real knowledge is to know the extent of one’s ignorance."
    ― Confucius

    "The realization of ignorance is the first act of knowing."
    ― Jean Toomer
    Reply With Quote

  10. #10
    500 Internal Server Error jujuB's Avatar
    Join Date: Apr 2008
    Location: Georgia, United States
    Stats: 6'0", 200 lbs
    Posts: 17,544
    Rep Power: 36008
    jujuB has much to be proud of. One of the best! (+20000) jujuB has much to be proud of. One of the best! (+20000) jujuB has much to be proud of. One of the best! (+20000) jujuB has much to be proud of. One of the best! (+20000) jujuB has much to be proud of. One of the best! (+20000) jujuB has much to be proud of. One of the best! (+20000) jujuB has much to be proud of. One of the best! (+20000) jujuB has much to be proud of. One of the best! (+20000) jujuB has much to be proud of. One of the best! (+20000) jujuB has much to be proud of. One of the best! (+20000) jujuB has much to be proud of. One of the best! (+20000)
    jujuB is offline
    well

    torque = force x lever arm (radius?)

    you on the mastering physics thing?
    RIP mainsqueeze530 1991-2013
    Reply With Quote

  11. #11
    Hey im polish too Deathstriker666's Avatar
    Join Date: Feb 2007
    Location: Australia
    Age: 25
    Stats: 5'9", 167 lbs
    Posts: 4,591
    BodyPoints: 418
    Rep Power: 785
    Deathstriker666 is a jewel in the rough. (+500) Deathstriker666 is a jewel in the rough. (+500) Deathstriker666 is a jewel in the rough. (+500) Deathstriker666 is a jewel in the rough. (+500) Deathstriker666 is a jewel in the rough. (+500) Deathstriker666 is a jewel in the rough. (+500) Deathstriker666 is a jewel in the rough. (+500) Deathstriker666 is a jewel in the rough. (+500) Deathstriker666 is a jewel in the rough. (+500) Deathstriker666 is a jewel in the rough. (+500) Deathstriker666 is a jewel in the rough. (+500)
    Deathstriker666 is offline
    ill do it mann, ill edit this post when im done. edit: for q6, the radious of the sphere isnt given. So the energy cant be worked out.
    Reply With Quote

  12. #12
    Old School Lunatic's Avatar
    Join Date: Feb 2106
    Location: United States
    Stats: 2'7", 205 lbs
    Posts: 47,421
    BodyPoints: 36180
    Rep Power: 246367
    Lunatic has a reputation beyond repute. Second best rank possible! (+100000) Lunatic has a reputation beyond repute. Second best rank possible! (+100000) Lunatic has a reputation beyond repute. Second best rank possible! (+100000) Lunatic has a reputation beyond repute. Second best rank possible! (+100000) Lunatic has a reputation beyond repute. Second best rank possible! (+100000) Lunatic has a reputation beyond repute. Second best rank possible! (+100000) Lunatic has a reputation beyond repute. Second best rank possible! (+100000) Lunatic has a reputation beyond repute. Second best rank possible! (+100000) Lunatic has a reputation beyond repute. Second best rank possible! (+100000) Lunatic has a reputation beyond repute. Second best rank possible! (+100000) Lunatic has a reputation beyond repute. Second best rank possible! (+100000)
    Lunatic is offline
    Originally Posted by juju_BEAN View Post
    well

    torque = force x lever arm (radius?)

    you on the mastering physics thing?
    It's WebAssign. Get 4 chances to do the problem before it being counted against you.

    Originally Posted by Deathstriker666 View Post
    ill do it mann, ill edit this post when im done. edit: for q6, the radious of the sphere isnt given. So the energy cant be worked out.
    I copy and pasted so I dunno
    || LSU Tigers || New Orleans Saints || Washington Nationals || LOL at basketball ||

    Mechanical Engineer in training

    “We are all born ignorant, but one must work hard to remain stupid.”
    ― Benjamin Franklin

    "Real knowledge is to know the extent of one’s ignorance."
    ― Confucius

    "The realization of ignorance is the first act of knowing."
    ― Jean Toomer
    Reply With Quote

  13. #13
    Registered User ausluke's Avatar
    Join Date: Oct 2008
    Location: Sydney, NSW, Australia
    Age: 26
    Stats: 5'6", 143 lbs
    Posts: 6,359
    Rep Power: 2772
    ausluke is a glorious beacon of knowledge. (+2500) ausluke is a glorious beacon of knowledge. (+2500) ausluke is a glorious beacon of knowledge. (+2500) ausluke is a glorious beacon of knowledge. (+2500) ausluke is a glorious beacon of knowledge. (+2500) ausluke is a glorious beacon of knowledge. (+2500) ausluke is a glorious beacon of knowledge. (+2500) ausluke is a glorious beacon of knowledge. (+2500) ausluke is a glorious beacon of knowledge. (+2500) ausluke is a glorious beacon of knowledge. (+2500) ausluke is a glorious beacon of knowledge. (+2500)
    ausluke is offline
    2) 0.002169648 J
    havn't done physics since high school so probably isn't correct but i dunno maybe :P
    Reply With Quote

  14. #14
    Old School Lunatic's Avatar
    Join Date: Feb 2106
    Location: United States
    Stats: 2'7", 205 lbs
    Posts: 47,421
    BodyPoints: 36180
    Rep Power: 246367
    Lunatic has a reputation beyond repute. Second best rank possible! (+100000) Lunatic has a reputation beyond repute. Second best rank possible! (+100000) Lunatic has a reputation beyond repute. Second best rank possible! (+100000) Lunatic has a reputation beyond repute. Second best rank possible! (+100000) Lunatic has a reputation beyond repute. Second best rank possible! (+100000) Lunatic has a reputation beyond repute. Second best rank possible! (+100000) Lunatic has a reputation beyond repute. Second best rank possible! (+100000) Lunatic has a reputation beyond repute. Second best rank possible! (+100000) Lunatic has a reputation beyond repute. Second best rank possible! (+100000) Lunatic has a reputation beyond repute. Second best rank possible! (+100000) Lunatic has a reputation beyond repute. Second best rank possible! (+100000)
    Lunatic is offline
    I have this one worked out but it's wrong. I did it the same way my fraternity brother did it but I got it wrong and he got it right.

    What is the rotational inertia of a solid iron disk of mass 47 kg, with a thickness of 6.16 cm and radius of 18.8 cm, about an axis through its center and perpendicular to it?

    Any help? All other problems are done.
    || LSU Tigers || New Orleans Saints || Washington Nationals || LOL at basketball ||

    Mechanical Engineer in training

    “We are all born ignorant, but one must work hard to remain stupid.”
    ― Benjamin Franklin

    "Real knowledge is to know the extent of one’s ignorance."
    ― Confucius

    "The realization of ignorance is the first act of knowing."
    ― Jean Toomer
    Reply With Quote

  15. #15
    Registered User colt.45's Avatar
    Join Date: Sep 2007
    Age: 26
    Posts: 11,197
    BodyPoints: 11537
    Rep Power: 1866
    colt.45 is just really nice. (+1000) colt.45 is just really nice. (+1000) colt.45 is just really nice. (+1000) colt.45 is just really nice. (+1000) colt.45 is just really nice. (+1000) colt.45 is just really nice. (+1000) colt.45 is just really nice. (+1000) colt.45 is just really nice. (+1000) colt.45 is just really nice. (+1000) colt.45 is just really nice. (+1000) colt.45 is just really nice. (+1000)
    colt.45 is offline
    Last year I knew al this ****, now I cant remember a damn thing
    Reply With Quote

  16. #16
    Old School Lunatic's Avatar
    Join Date: Feb 2106
    Location: United States
    Stats: 2'7", 205 lbs
    Posts: 47,421
    BodyPoints: 36180
    Rep Power: 246367
    Lunatic has a reputation beyond repute. Second best rank possible! (+100000) Lunatic has a reputation beyond repute. Second best rank possible! (+100000) Lunatic has a reputation beyond repute. Second best rank possible! (+100000) Lunatic has a reputation beyond repute. Second best rank possible! (+100000) Lunatic has a reputation beyond repute. Second best rank possible! (+100000) Lunatic has a reputation beyond repute. Second best rank possible! (+100000) Lunatic has a reputation beyond repute. Second best rank possible! (+100000) Lunatic has a reputation beyond repute. Second best rank possible! (+100000) Lunatic has a reputation beyond repute. Second best rank possible! (+100000) Lunatic has a reputation beyond repute. Second best rank possible! (+100000) Lunatic has a reputation beyond repute. Second best rank possible! (+100000)
    Lunatic is offline
    Originally Posted by ausluke View Post
    2) 0.002169648 J
    havn't done physics since high school so probably isn't correct but i dunno maybe :P
    **** yoooooooooooou didn't work
    || LSU Tigers || New Orleans Saints || Washington Nationals || LOL at basketball ||

    Mechanical Engineer in training

    “We are all born ignorant, but one must work hard to remain stupid.”
    ― Benjamin Franklin

    "Real knowledge is to know the extent of one’s ignorance."
    ― Confucius

    "The realization of ignorance is the first act of knowing."
    ― Jean Toomer
    Reply With Quote

  17. #17
    Registered User dantheman999's Avatar
    Join Date: May 2008
    Location: Canada
    Age: 30
    Stats: 5'9", 198 lbs
    Posts: 4,444
    Rep Power: 1042
    dantheman999 is a jewel in the rough. (+500) dantheman999 is a jewel in the rough. (+500) dantheman999 is a jewel in the rough. (+500) dantheman999 is a jewel in the rough. (+500) dantheman999 is a jewel in the rough. (+500) dantheman999 is a jewel in the rough. (+500) dantheman999 is a jewel in the rough. (+500) dantheman999 is a jewel in the rough. (+500) dantheman999 is a jewel in the rough. (+500) dantheman999 is a jewel in the rough. (+500) dantheman999 is a jewel in the rough. (+500)
    dantheman999 is offline
    To late to give it a shot?

    Master mech eng here.

    EDIT: I see the time now, seems i missed it. Theres no way anyone could have answered all those in 8 minutes, unless they work on this **** regularly. Probably take half an hour just to look up the stuff again.
    Reply With Quote

  18. #18
    Registered User Abitofmuscle's Avatar
    Join Date: Mar 2008
    Posts: 2,186
    Rep Power: 3680
    Abitofmuscle is a glorious beacon of knowledge. (+2500) Abitofmuscle is a glorious beacon of knowledge. (+2500) Abitofmuscle is a glorious beacon of knowledge. (+2500) Abitofmuscle is a glorious beacon of knowledge. (+2500) Abitofmuscle is a glorious beacon of knowledge. (+2500) Abitofmuscle is a glorious beacon of knowledge. (+2500) Abitofmuscle is a glorious beacon of knowledge. (+2500) Abitofmuscle is a glorious beacon of knowledge. (+2500) Abitofmuscle is a glorious beacon of knowledge. (+2500) Abitofmuscle is a glorious beacon of knowledge. (+2500) Abitofmuscle is a glorious beacon of knowledge. (+2500)
    Abitofmuscle is offline
    For the last one with the picture I got

    A = 2.148 KN downward
    B = 3.296 KN upward

    I assumed that you represent the mass of the board as a concentrated force in the middle of the board.

    If you use distributed forces for weights then the answers would change.
    Reply With Quote

  19. #19
    Old School Lunatic's Avatar
    Join Date: Feb 2106
    Location: United States
    Stats: 2'7", 205 lbs
    Posts: 47,421
    BodyPoints: 36180
    Rep Power: 246367
    Lunatic has a reputation beyond repute. Second best rank possible! (+100000) Lunatic has a reputation beyond repute. Second best rank possible! (+100000) Lunatic has a reputation beyond repute. Second best rank possible! (+100000) Lunatic has a reputation beyond repute. Second best rank possible! (+100000) Lunatic has a reputation beyond repute. Second best rank possible! (+100000) Lunatic has a reputation beyond repute. Second best rank possible! (+100000) Lunatic has a reputation beyond repute. Second best rank possible! (+100000) Lunatic has a reputation beyond repute. Second best rank possible! (+100000) Lunatic has a reputation beyond repute. Second best rank possible! (+100000) Lunatic has a reputation beyond repute. Second best rank possible! (+100000) Lunatic has a reputation beyond repute. Second best rank possible! (+100000)
    Lunatic is offline
    Originally Posted by dantheman999 View Post
    To late to give it a shot?

    Master mech eng here.
    got 37 minutes!!
    || LSU Tigers || New Orleans Saints || Washington Nationals || LOL at basketball ||

    Mechanical Engineer in training

    “We are all born ignorant, but one must work hard to remain stupid.”
    ― Benjamin Franklin

    "Real knowledge is to know the extent of one’s ignorance."
    ― Confucius

    "The realization of ignorance is the first act of knowing."
    ― Jean Toomer
    Reply With Quote

  20. #20
    Registered User colt.45's Avatar
    Join Date: Sep 2007
    Age: 26
    Posts: 11,197
    BodyPoints: 11537
    Rep Power: 1866
    colt.45 is just really nice. (+1000) colt.45 is just really nice. (+1000) colt.45 is just really nice. (+1000) colt.45 is just really nice. (+1000) colt.45 is just really nice. (+1000) colt.45 is just really nice. (+1000) colt.45 is just really nice. (+1000) colt.45 is just really nice. (+1000) colt.45 is just really nice. (+1000) colt.45 is just really nice. (+1000) colt.45 is just really nice. (+1000)
    colt.45 is offline
    Originally Posted by dantheman999 View Post
    To late to give it a shot?

    Master mech eng here.
    wat school brah?
    Reply With Quote

  21. #21
    Old School Lunatic's Avatar
    Join Date: Feb 2106
    Location: United States
    Stats: 2'7", 205 lbs
    Posts: 47,421
    BodyPoints: 36180
    Rep Power: 246367
    Lunatic has a reputation beyond repute. Second best rank possible! (+100000) Lunatic has a reputation beyond repute. Second best rank possible! (+100000) Lunatic has a reputation beyond repute. Second best rank possible! (+100000) Lunatic has a reputation beyond repute. Second best rank possible! (+100000) Lunatic has a reputation beyond repute. Second best rank possible! (+100000) Lunatic has a reputation beyond repute. Second best rank possible! (+100000) Lunatic has a reputation beyond repute. Second best rank possible! (+100000) Lunatic has a reputation beyond repute. Second best rank possible! (+100000) Lunatic has a reputation beyond repute. Second best rank possible! (+100000) Lunatic has a reputation beyond repute. Second best rank possible! (+100000) Lunatic has a reputation beyond repute. Second best rank possible! (+100000)
    Lunatic is offline
    Originally Posted by Abitofmuscle View Post
    For the last one with the picture I got

    A = 2.148 KN downward
    B = 3.296 KN upward

    I assumed that you represent the mass of the board as a concentrated force in the middle of the board.

    If you use distributed forces for weights then the answers would change.
    I ****ing love you. Repped. Care to try others?
    || LSU Tigers || New Orleans Saints || Washington Nationals || LOL at basketball ||

    Mechanical Engineer in training

    “We are all born ignorant, but one must work hard to remain stupid.”
    ― Benjamin Franklin

    "Real knowledge is to know the extent of one’s ignorance."
    ― Confucius

    "The realization of ignorance is the first act of knowing."
    ― Jean Toomer
    Reply With Quote

  22. #22
    Crazy Asian tehmaestro's Avatar
    Join Date: Feb 2009
    Location: Auburn, Alabama, United States
    Age: 27
    Stats: 5'9", 160 lbs
    Posts: 180
    Rep Power: 1276
    tehmaestro is just really nice. (+1000) tehmaestro is just really nice. (+1000) tehmaestro is just really nice. (+1000) tehmaestro is just really nice. (+1000) tehmaestro is just really nice. (+1000) tehmaestro is just really nice. (+1000) tehmaestro is just really nice. (+1000) tehmaestro is just really nice. (+1000) tehmaestro is just really nice. (+1000) tehmaestro is just really nice. (+1000) tehmaestro is just really nice. (+1000)
    tehmaestro is offline
    Originally Posted by Abitofmuscle View Post
    For the last one with the picture I got

    A = 2.148 KN downward
    B = 3.296 KN upward

    I assumed that you represent the mass of the board as a concentrated force in the middle of the board.

    If you use distributed forces for weights then the answers would change.
    **** I just did this one, LOL
    Reply With Quote

  23. #23
    Registered User ausluke's Avatar
    Join Date: Oct 2008
    Location: Sydney, NSW, Australia
    Age: 26
    Stats: 5'6", 143 lbs
    Posts: 6,359
    Rep Power: 2772
    ausluke is a glorious beacon of knowledge. (+2500) ausluke is a glorious beacon of knowledge. (+2500) ausluke is a glorious beacon of knowledge. (+2500) ausluke is a glorious beacon of knowledge. (+2500) ausluke is a glorious beacon of knowledge. (+2500) ausluke is a glorious beacon of knowledge. (+2500) ausluke is a glorious beacon of knowledge. (+2500) ausluke is a glorious beacon of knowledge. (+2500) ausluke is a glorious beacon of knowledge. (+2500) ausluke is a glorious beacon of knowledge. (+2500) ausluke is a glorious beacon of knowledge. (+2500)
    ausluke is offline
    6a) 8.42J
    if thats not right i dunno what is!
    Reply With Quote

  24. #24
    Crazy Asian tehmaestro's Avatar
    Join Date: Feb 2009
    Location: Auburn, Alabama, United States
    Age: 27
    Stats: 5'9", 160 lbs
    Posts: 180
    Rep Power: 1276
    tehmaestro is just really nice. (+1000) tehmaestro is just really nice. (+1000) tehmaestro is just really nice. (+1000) tehmaestro is just really nice. (+1000) tehmaestro is just really nice. (+1000) tehmaestro is just really nice. (+1000) tehmaestro is just really nice. (+1000) tehmaestro is just really nice. (+1000) tehmaestro is just really nice. (+1000) tehmaestro is just really nice. (+1000) tehmaestro is just really nice. (+1000)
    tehmaestro is offline
    6b) is 1.421m
    Reply With Quote

  25. #25
    Registered User colt.45's Avatar
    Join Date: Sep 2007
    Age: 26
    Posts: 11,197
    BodyPoints: 11537
    Rep Power: 1866
    colt.45 is just really nice. (+1000) colt.45 is just really nice. (+1000) colt.45 is just really nice. (+1000) colt.45 is just really nice. (+1000) colt.45 is just really nice. (+1000) colt.45 is just really nice. (+1000) colt.45 is just really nice. (+1000) colt.45 is just really nice. (+1000) colt.45 is just really nice. (+1000) colt.45 is just really nice. (+1000) colt.45 is just really nice. (+1000)
    colt.45 is offline
    Originally Posted by ausluke View Post
    6a) 8.42J
    if thats not right i dunno what is!
    unless you took into account the moment of intertia its gonna be wrong.

    You need the term 1/2Iw^2 as well as 1/2mv^2 in there I'm fairly sure
    Reply With Quote

  26. #26
    Registered User Abitofmuscle's Avatar
    Join Date: Mar 2008
    Posts: 2,186
    Rep Power: 3680
    Abitofmuscle is a glorious beacon of knowledge. (+2500) Abitofmuscle is a glorious beacon of knowledge. (+2500) Abitofmuscle is a glorious beacon of knowledge. (+2500) Abitofmuscle is a glorious beacon of knowledge. (+2500) Abitofmuscle is a glorious beacon of knowledge. (+2500) Abitofmuscle is a glorious beacon of knowledge. (+2500) Abitofmuscle is a glorious beacon of knowledge. (+2500) Abitofmuscle is a glorious beacon of knowledge. (+2500) Abitofmuscle is a glorious beacon of knowledge. (+2500) Abitofmuscle is a glorious beacon of knowledge. (+2500) Abitofmuscle is a glorious beacon of knowledge. (+2500)
    Abitofmuscle is offline
    Originally Posted by Lunatic View Post
    I ****ing love you. Repped. Care to try others?
    Can't figure out the others. I'm sure some misc physics guru brahs will come to help though.
    Reply With Quote

  27. #27
    Registered User ausluke's Avatar
    Join Date: Oct 2008
    Location: Sydney, NSW, Australia
    Age: 26
    Stats: 5'6", 143 lbs
    Posts: 6,359
    Rep Power: 2772
    ausluke is a glorious beacon of knowledge. (+2500) ausluke is a glorious beacon of knowledge. (+2500) ausluke is a glorious beacon of knowledge. (+2500) ausluke is a glorious beacon of knowledge. (+2500) ausluke is a glorious beacon of knowledge. (+2500) ausluke is a glorious beacon of knowledge. (+2500) ausluke is a glorious beacon of knowledge. (+2500) ausluke is a glorious beacon of knowledge. (+2500) ausluke is a glorious beacon of knowledge. (+2500) ausluke is a glorious beacon of knowledge. (+2500) ausluke is a glorious beacon of knowledge. (+2500)
    ausluke is offline
    lol then its wrong
    Reply With Quote

  28. #28
    Old School Lunatic's Avatar
    Join Date: Feb 2106
    Location: United States
    Stats: 2'7", 205 lbs
    Posts: 47,421
    BodyPoints: 36180
    Rep Power: 246367
    Lunatic has a reputation beyond repute. Second best rank possible! (+100000) Lunatic has a reputation beyond repute. Second best rank possible! (+100000) Lunatic has a reputation beyond repute. Second best rank possible! (+100000) Lunatic has a reputation beyond repute. Second best rank possible! (+100000) Lunatic has a reputation beyond repute. Second best rank possible! (+100000) Lunatic has a reputation beyond repute. Second best rank possible! (+100000) Lunatic has a reputation beyond repute. Second best rank possible! (+100000) Lunatic has a reputation beyond repute. Second best rank possible! (+100000) Lunatic has a reputation beyond repute. Second best rank possible! (+100000) Lunatic has a reputation beyond repute. Second best rank possible! (+100000) Lunatic has a reputation beyond repute. Second best rank possible! (+100000)
    Lunatic is offline
    Originally Posted by ausluke View Post
    6a) 8.42J
    if thats not right i dunno what is!
    Originally Posted by tehmaestro View Post
    6b) is 1.421m
    Both wrong
    || LSU Tigers || New Orleans Saints || Washington Nationals || LOL at basketball ||

    Mechanical Engineer in training

    “We are all born ignorant, but one must work hard to remain stupid.”
    ― Benjamin Franklin

    "Real knowledge is to know the extent of one’s ignorance."
    ― Confucius

    "The realization of ignorance is the first act of knowing."
    ― Jean Toomer
    Reply With Quote

  29. #29
    Hey im polish too Deathstriker666's Avatar
    Join Date: Feb 2007
    Location: Australia
    Age: 25
    Stats: 5'9", 167 lbs
    Posts: 4,591
    BodyPoints: 418
    Rep Power: 785
    Deathstriker666 is a jewel in the rough. (+500) Deathstriker666 is a jewel in the rough. (+500) Deathstriker666 is a jewel in the rough. (+500) Deathstriker666 is a jewel in the rough. (+500) Deathstriker666 is a jewel in the rough. (+500) Deathstriker666 is a jewel in the rough. (+500) Deathstriker666 is a jewel in the rough. (+500) Deathstriker666 is a jewel in the rough. (+500) Deathstriker666 is a jewel in the rough. (+500) Deathstriker666 is a jewel in the rough. (+500) Deathstriker666 is a jewel in the rough. (+500)
    Deathstriker666 is offline
    Originally Posted by Lunatic View Post
    I have this one worked out but it's wrong. I did it the same way my fraternity brother did it but I got it wrong and he got it right.

    What is the rotational inertia of a solid iron disk of mass 47 kg, with a thickness of 6.16 cm and radius of 18.8 cm, about an axis through its center and perpendicular to it?

    Any help? All other problems are done.
    = I = 0.5m(r^2)
    = 0.830584, assuming the axis is down the middle. If its like through the side

    I = (1/12)m(3(r^2)+(h^2))
    = 0.45987808
    Reply With Quote

  30. #30
    Old School Lunatic's Avatar
    Join Date: Feb 2106
    Location: United States
    Stats: 2'7", 205 lbs
    Posts: 47,421
    BodyPoints: 36180
    Rep Power: 246367
    Lunatic has a reputation beyond repute. Second best rank possible! (+100000) Lunatic has a reputation beyond repute. Second best rank possible! (+100000) Lunatic has a reputation beyond repute. Second best rank possible! (+100000) Lunatic has a reputation beyond repute. Second best rank possible! (+100000) Lunatic has a reputation beyond repute. Second best rank possible! (+100000) Lunatic has a reputation beyond repute. Second best rank possible! (+100000) Lunatic has a reputation beyond repute. Second best rank possible! (+100000) Lunatic has a reputation beyond repute. Second best rank possible! (+100000) Lunatic has a reputation beyond repute. Second best rank possible! (+100000) Lunatic has a reputation beyond repute. Second best rank possible! (+100000) Lunatic has a reputation beyond repute. Second best rank possible! (+100000)
    Lunatic is offline
    Originally Posted by Deathstriker666 View Post
    = I = 0.5m(r^2)
    = 0.830584, assuming the axis is down the middle. If its like through the side

    I = (1/12)m(3(r^2)+(h^2))
    = 0.45987808
    So which is the answer?
    || LSU Tigers || New Orleans Saints || Washington Nationals || LOL at basketball ||

    Mechanical Engineer in training

    “We are all born ignorant, but one must work hard to remain stupid.”
    ― Benjamin Franklin

    "Real knowledge is to know the extent of one’s ignorance."
    ― Confucius

    "The realization of ignorance is the first act of knowing."
    ― Jean Toomer
    Reply With Quote

Similar Threads

  1. Need Physics Help (REPS)
    By agile321 in forum Misc.
    Replies: 6
    Last Post: 02-26-2009, 02:50 PM
  2. Replies: 21
    Last Post: 11-25-2008, 06:44 PM
  3. Need physics help (free falling) (reps)
    By agile321 in forum Misc.
    Replies: 25
    Last Post: 10-14-2008, 06:25 PM
  4. Need physics help! (reps)
    By jaberocs in forum Misc.
    Replies: 13
    Last Post: 09-12-2008, 02:02 AM
  5. I need physics help! (reps and thanks!)
    By gr8fubar420 in forum Misc.
    Replies: 2
    Last Post: 03-05-2007, 05:19 PM

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts