A 30-N box is pulled upward 6.0 m along the surface of a ramp that rises at $37 ^ { \circ }$ above the horizontal. How much work does gravity do on the box during this process?
A) -110 J
B) -140 J
C) -1100 J
D) -180 J
E) 120 J

Question

A  30-N box is pulled upward  6.0 m along the surface of a ramp that rises at $37 ^ { \circ }$ above the horizontal. How much work does gravity do on the box during this process?
A)  -110 J
B)  -140 J
C)  -1100 J
D)  -180 J
E)  120 J

Quizplus · Accepted Answer

The work done by gravity is calculated using the formula $W = -mgd \cos(\theta)$, where $m$ is the mass, $g$ is the acceleration due to gravity (9.8 m/s$^2$), $d$ is the distance moved, and $\theta$ is the angle of the incline. Here, the force due to gravity (weight) is given as 30 N, so $m = 30/g$, and $d = 6.0$ m, $\theta = 37^\circ$. Substituting these values, we find $W = -30 \times 6 \times \cos(37^\circ)$, which approximates to -110 J.

A 30-N Box Is Pulled Upward 6 37∘37 ^ { \circ }37∘

A 30-N Box Is Pulled Upward 6 $37 ^ { \circ }$