Question

An ant moves along a circular thread with speed $10\frac{cm}{s}$. It covers one cycle in 10 minutes. Chintu is a naughty boy who cut the thread to make it a straight line and challenges ant to reach the end in half the time. What should be the constant acceleration that ant should maintain to complete his challenge?

• A. (1/500) m/s²
• B. (1/750) m/s²
• C. (1/1000) m/s²
• D. (1/1500) m/s²

Answer 1

The correct option is B

(1/750) m/s²

Length of thread = speed $\times$ time = (0.1) $\times$ (10 $\times$ 60) = 60 m

Now the ant has to cover distance 60 m in half the time, i.e. 5 minutes

Using second equation of motion, $s=ut+\frac{1}{2}a{t}^2$

$60=0+\frac{1}{2}\times a\times (60\times 5{)}^2$

On solving we get, $a=\frac{1}{750}$ ${\frac{m}{s}}^2$