Question

A 25 kg box sliding to the left across a horizontal surface is brought to a halt in a distance of 35 cm by a horizontal rope pulling to the right with 15 N tension. How much work is done by (a) tension and (b) gravity?

Short answer

a) 5.25 J

b) 0 J

Step-by-step solution

Part(a) Step 1: Given information

25 kg box sliding to the left across a horizontal surface is brought to a halt in a distance of 35 cm by a horizontal rope pulling to the right with 15 N tension .

Part(a) Step 2: Explanation

Work done = Force x Displacement in the direction.

W = F x d

Work done by tension = tension x distance

W_tension = 15 x 0.35=5.25 J

Part(b) Step 1 : Given information

25 kg box sliding to the left across a horizontal surface is brought to a halt in a distance of 35 cm by a horizontal rope pulling to the right with 15 N tension .

Part(b) Step 2: Explanation

Work done = Force x displacement in the direction of force.

W= F x d

Gravitational force = mg =25 x 9.81=245.25 N
Vertical displacement =0
Work done by gravity, W_gravity = 0 J