Question

A boy stretches a stone against the rubber tape of a catapult or 'gulel' (a device used to detach mangoes from the tree by boys in Indian villages) through a distance of $24\text{cm}$ before leaving it. The tape returns to its initial normal position, accelerating the stone over the stretched length. The stone leaves the gulel with a speed of $2.2\text{m/s}$. Assuming that acceleration is constant while the stone was being pushed by the tape, find the magnitude.

• A. $8.1{\text{m/s}}^2$
• B. $9.1{\text{m/s}}^2$
• C. $10.1{\text{m/s}}^2$
• D. $11.1{\text{m/s}}^2$

Answer 1

The correct option is C $10.1{\text{m/s}}^2$

Consider the accelerated $24\text{cm}$ motion of the stone.
Initial velocity $=0\text{m/s}$
Final velocity $=2.2\text{m/s}$
Distance travelled $=24\text{cm}=0.24\text{m}$
using, ${\text{v}}^2={\text{u}}^2+2\text{.a.s}$
$\text{a}=\frac{4.84{\text{(m/s)}}^2}{2\times 0.24\text{m}}=10.1{\text{m/s}}^2$