Question

A boulder with a mass of 25 kilograms slides 30 meters to the right white experiencing sight force of 150 newtons and a leftward force of friction that is two thirds the magnitude of the force 1. Calculate the magnitude of work done by the force of friction A. O joules B. 1500 joules C 3000 joules D. 4500 joules It takes the boulder 5.48 seconds to travel 30 meters 2. Calculate the power required to move the boulder 30 meters. A. 273.7 watts B. 547.4 watts C. 1500 watts D. 3000 watts​

Answer 1

Answer:

(1) 1500 J (2) 273.7 W

Explanation:

Given that,

The mass of a boulder, m = 25 kg

Distance moved by the force, d = 30 m

Applied force, F = 150 N

As a leftward force of friction that is two thirds the magnitude of the force, f = 100

Net force = 50 N

(1) Work done by the force is equal to the product of force and displacement i.e.

W = Fd

Put all the values,

W = 50 × 30

W = 1500 J

(2) It takes the boulder 5.48 seconds to travel 30 meters.

Power, P = W/t

So,

$P=\dfrac{1500}{5.48}\\\\P=273.7\ W$