A small block of mass `100 g` moves with uniform speed in a horizontal circular groove, with vertical side walls of radius `25cm`. If the block takes `2.0 s` to complete one round, find the constant force by the side wall of the groove.

Answer

A, B, D

Explanation

The sped of the block is
`v=(2pixx(25 cm))/(2.0s) =0.785 m//s`
The acceleration of the block is
`a=(v^(2))/r=((0.785m//s)^(2))/(0.25 m)=2.464 m//s^(2)`
towards the centre, the only force in this direction is the normal contact force due to the side walls. thus, from Newton's second law, this force is
`N=ma=(0.100 kg) (2.464 m//s^(2))=0.246N`