Question

A light string passes over a frictionless pulley. To one of its ends a mass of 6 kg is attached. To its other end a mass of 10 kg is attached. The tension in the thread will be [RPET 1996; JIPMER 2001, 02]
A) 24.5 N B) 2.45 N C) 79 N D) 73.5 N

Answer 1

Let m₁ = 6kg and m₂ = 10kg
10 kg mass is heavier than 6 kg mass . So, 6 kg moves upward and 10 kg moves downward.
Let acceleration generated due to motion of bodies is a

Now, apply Newton's 2nd law,
For 1st body ,
T - m₁g = m₁a ----(1)

For 2nd body,
m₂g - T = m₂a -----(2)

Solving both equations
we get , T = 2m₁m₂g/(m₁ + m₂)

Now, put the values of m₁, m₂ and g
e.g., T = 2 × 6 × 10 × 9.8/(6 + 10)
T = 12 × 98/16
T = 294/4 N = 73.5 N

Hence, tension in string = 73.5 N
∴ option (d) is correct.

Answer 2

Answer:

D

Explanation:

use 2 and law of motion to get the answer

we get 73.5N