Question

Two blocks of masses 8 kg and 12 kg kept on a smooth horizontal table are connected to the ends of a light string as shown in the figure. If a horizontal force of 500 N is applied to the block of mass 12 kg, then the tension in the string connecting the blocks is

• A. 200 N
• B. 300 N
• C. 500 N
• D. 250 N

Hint:

When multiple blocks are connected and a net force is applied to one, use total mass to find acceleration, then apply Newton’s Second Law to individual blocks to find tension.

Answer 1

The Correct Option is A

Step 1: Total mass of the system = \(8 + 12 = 20\ \text{kg}\) Step 2: Acceleration of the system: \[ a = \frac{F}{m} = \frac{500}{20} = 25\ \text{m/s}^2 \] Step 3: Tension acts on the 8 kg block to accelerate it: \[ T = m a = 8 \times 25 = 200\ \text{N} \]