Question

In the figure shown, the forces are acting simultaneously on the body of mass $10\text{kg}$ which is initially at rest. Find its velocity after $10\text{s}$.

• A. $10\text{m/s}$
• B. $20\text{m/s}$
• C. $25\text{m/s}$
• D. $30\text{m/s}$

Answer 1

The correct option is C $25\text{m/s}$

Net force on the system will be
$\Sigma F=20+10-5=25\text{N}\Sigma F=ma\Rightarrow a=\frac{25}{10}=2.5{\text{m/s}}^2$
Now, we can use $1^{st}$ equation of motion to find velocity
$v=u+at=2.5\times 10=25\text{m/s}$