Problem 6-11 Dynamics with friction - Part 4 - C

A child is sliding down a water slide inclined at 25 to the horizontal. The coefficient of kinetic friction between the child and the slide is 0.10. What is the magnitude of the acceleration of the child? (Hint: FN is not equal to mg.)


Accumulated Solution

FBD with all forces, directions and angles indicated.


Correct! Fy=FNmgcos25=0

Therefore FN=mgcos25 and f=μFN=(0.10)(m)(9.8)cos25=0.888m

The correct expression in the x-direction is:

(A)   mgf=ma

(B)   mgcos25f=ma

(C)   mgsin25f=ma