Author Topic: Mechanics Question!!  (Read 700 times)

Offline mousa

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Mechanics Question!!
« on: November 29, 2009, 02:14:28 pm »
hey everyone.. well i got stuck on a cie mechanics question.. it soundzz simple( the question).. but i dunno why i am getting stuck on it!! well ,  here is the question :)

A shopper picks up a 2Kg packet of  rice with the thumb and index finger of one hand .The coefficient of friction between her fingers and the wrapping is 0.3. What horizontal force must she exert to prevent the packet from slipping!

help!!

Offline astarmathsandphysics

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Re: Mechanics Question!!
« Reply #1 on: November 29, 2009, 02:58:56 pm »
2g/2*0.3=g/0.3

Offline spiderman

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Re: Mechanics Question!!
« Reply #2 on: November 30, 2009, 12:27:30 pm »
Hey Mousa,
heres the answer to ur question........

Limiting friction= mew * 2N(2times normal contact foce as she is using 2 fingers)
20 = 0.3*2N
20/0.3=2N
2N=66.67
N=33.33N
Hence the horizontal force she needs to apply to prevent the rice fromslipping is 33.33N

Hope this helped.........
Always hangin around ur neighbourhood..........