Question

A force of 10 N acts on a body of mass 2 kg in the direction of motion of the body. If the velocity of the body at a time \( t = 0 \) is \( 13\,{ms}^{-1} \), then the velocity of the body at time \( t = 3\,{s} \) is

• A. \( 20\,{ms}^{-1} \)
• B. \( 24\,{ms}^{-1} \)
• C. \( 28\,{ms}^{-1} \)
• D. \( 32\,{ms}^{-1} \)

Hint:

Use the equation \( v = u + at \) when force and mass are given and the force acts in the direction of motion.

Answer 1

The Correct Option is C

Force \( F = 10\,{N} \), Mass \( m = 2\,{kg} \)
Acceleration \( a = \frac{F}{m} = \frac{10}{2} = 5\,{ms}^{-2} \)
Initial velocity \( u = 13\,{ms}^{-1} \), Time \( t = 3\,{s} \)
Final velocity \( v = u + at = 13 + 5 \times 3 = 28\,{ms}^{-1} \)