Question

A body of mass $1kg$ is traveling with a velocity of $3m/s$ accelerates uniformly to acquire a velocity of $8m/s$ in $2s$. Find the force acting on the body.

• A. $3\text{N}$
• B. $2\text{N}$
• C. $2.5\text{N}$
• D. $5\text{N}$

Answer 1

The correct option is C $2.5\text{N}$

Acceleration $=\frac{\text{Change in velocity}}{\text{Time}}$
Thus, $a=\frac{8-3}{2}=2.5{\text{m/s}}^2$
$\therefore F=ma=1\text{kg}\times 2.5{\text{m/s}}^2=2.5\text{N}$