Question

To move a roller, a force of $300N$ is required. You alone can produce a force of $30N$. How many of your friends who are equally strong as you should join you to move the roller?

• A. 9
• B. 10
• C. 5
• D. None of these

Answer 1

Answer: (A)

9

Force applied by you $=30N=$ force applied by any of your friends.
So, let there be $x$ people in total to push the roller.
When $x$ people, each giving a force of $30N$, give force in same direction, total force = $(30\times x)$ newton
To move the roller, $30x=300$
So, $x=\frac{300}{30}=10$
$\therefore$ number of friends to join you $=(10-1)=9$ (excluding you)