Question

A frictionless cart starts at rest and accelerates down a straight incline of angle $\theta ={30.0}^o$ relative to the horizontal. The cart has mass $3.0kg$.
How much force does the cart exert on the incline?

• A. $14.7N$
• B. $17.0N$
• C. $25.5N$
• D. $29.4N$
• E. It depends on the speed of the cart at any given point in time

Answer 1

The correct option is C $25.5N$

Given : $m=3.0$ kg $g=9.8$ $m/s$

From figure, the force exerted by cart $R=mg$ $cos{30}^o=3.0\times 9.8\times 0.866=25.5$ N