Consider the sock in the spinning washer. Assume it does not move with respect t
ID: 1536630 • Letter: C
Question
Consider the sock in the spinning washer. Assume it does not move with respect to the washer walls and that the rotation axis is horizontal. Say the washer is spinning at 1000 rpm (rather typical); the radius of the wall is 0.3 meters; and the wet sock has a mass of 0.25 kg. a) If the sock is at a point in its rotation where the washer surface is vertical, what is the force the washer wall exerts on the sock? Give the horizontal and vertical components. b) What is the difference between the normal force at the top of the circular rotation, and the normal force at the bottom of the circular rotation? Consider the sock in the spinning washer. Assume it does not move with respect to the washer walls and that the rotation axis is horizontal. Say the washer is spinning at 1000 rpm (rather typical); the radius of the wall is 0.3 meters; and the wet sock has a mass of 0.25 kg. a) If the sock is at a point in its rotation where the washer surface is vertical, what is the force the washer wall exerts on the sock? Give the horizontal and vertical components. b) What is the difference between the normal force at the top of the circular rotation, and the normal force at the bottom of the circular rotation? Consider the sock in the spinning washer. Assume it does not move with respect to the washer walls and that the rotation axis is horizontal. Say the washer is spinning at 1000 rpm (rather typical); the radius of the wall is 0.3 meters; and the wet sock has a mass of 0.25 kg. a) If the sock is at a point in its rotation where the washer surface is vertical, what is the force the washer wall exerts on the sock? Give the horizontal and vertical components. b) What is the difference between the normal force at the top of the circular rotation, and the normal force at the bottom of the circular rotation?Explanation / Answer
given
w = 1000 rpm
= 1000*2*pi/60
= 104.7 rad/s
r = 0.3 m
m = 0.25 kg
a) Fx = m*a_rad
= m*r*w^2
= 0.25*0.3*104.7^2
= 822 N
Fy = m*g
= 0.25*9.8
= 2.45 N
b) N_bottom = m*g + m*r*w^2
B_top = m*r*w^2 - m*g
N_bottom - N_top = (m*g + m*r*w^2) - (m*r*w^2 - m*g)
= 2*m*g
= 2*0.25*9.8
= 4.9 N