Question 126: Work, Energy and Power & Circular Motion

Question

A block of 200 g mass moves with a uniform speed in a horizontal circular groove, with vertical side walls of radius 20 cm. If the block takes 40 s to complete one round, the normal force by the side walls of the groove is :

Accepted Answer

Normal force will provide the necessary centripetal force.
$ \Rightarrow $ N = m$\omega$
2
R
Also, $\omega$ = ${{2\pi } \over t}$
N = (0.2)$\left( {{{4{\pi ^2}} \over {{T^2}}}} ight)$(0.2)
$ \Rightarrow $ N = 0.2 $	imes$ ${{4 	imes {{(3.14)}^2}} \over {{{(40)}^2}}}$ $	imes$ 0.2
$ 	herefore $ N = 9.859 $	imes$ 10
$-$4
N

Answer

9.859 $	imes$ 10
$-$2
N

Answer

0.0314 N

Answer

9.859 $	imes$ 10
$-$4
N

Answer

6.28 $	imes$ 10
$-$3
N

Work, Energy and Power & Circular Motion

A block of 200 g mass moves with a uniform speed in a horizontal circular groove, with vertical side walls of radius 20 cm. If the block takes 40 s to complete one round, the normal force by the side walls of the groove is :

Choose the correct answer: