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Novay_Z [31]
3 years ago
9

A 20 kg crate of books is at rest on a table. what is the normal force on the books?

Physics
1 answer:
Umnica [9.8K]3 years ago
4 0

The weight of 20 kg is

                             (mass) x (gravity) =

                                   (20 x 9.8) = 196 newtons, downward.

There must be a force of 196 newtons upward on the mass. 
Otherwise the mass is accelerating either up or down.
 
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                          ( vf^2 - vi^2 ) = 2*g*R*( 1 - cos(θ))

                          vi^2 =  vf^2 - 2*g*R*( 1 - cos(θ))

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