Question

A load of bricks with mass m1 = 14.4 kg hangs from one end of a rope that passes over a small, frictionless pulley. A counterweight of mass m2 = 27.8 kg is suspended from the other end of the rope, as shown in the figure. (Figure 1) The system is released from rest. Use g = 9.80 m/s2 for the magnitude of the acceleration due to gravity.

(a)

What is the magnitude of the upward acceleration of the load of bricks?

(b)

What is the tension in the rope while the load is moving?

Answer 1

Here ,

m1 = 14.4 Kg

m2 = 27.8 Kg

a)

let the acceleration of bricks is a

Using second law of motion

(m1 + m2) * a = (m2 - m1) * g

(14.4 + 27.8) * a = (27.8 - 14.4) * 9.8

a = 3.12 m/s^2

the acceleration of bricks is 3.12 m/s^2

a)

let the tension in the rope is T

For m1

T - m1 * g = m1 * a

T - 14.4 * 9.8 = 14.4 * 3.12

T = 186.1 N

the tension in the cable is 186.1 N