Once the crate in sample problem d is in motion, a horizontal force of 53 n keeps the crate moving with constant velocity find the coefficient of kinetic friction between the crate and the floor

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m=24 kg, Ff=53 N, g=9.8 m/s^2,
use the formula Fg = mg,   Fg=24*9.8,
solve for Fg, Fg=235.2 N,
then use the formula Ff = ตkFn, 53=235.2ตk,
solve for ตk, ตk=.23

B. a circuit. i think

The objects do not reach terminal velocity         there is not enough time from the time the object falls from when it hits the ground to achieve terminal velocity. an object must be placed higher to achieve terminal velocity in order to be in free fall.