Question

A small stone of mass 0.4 kg tied to a massless
inextensible string is made to loop. The loop
radius of path is 4 m. Its minimum speed at the
highest point to complete vertical circular motion is
(1) 6.32 m/s
(2) Zero
(3) 5 m/s
(4) 3 m/s​

Answer 1

Answer:

Option (a) 6.32 m/s

Explanation:

Mass of the stone = 0.4 kg

Length of the string = 4 m

We know that

Minimum speed at the highest point to complete the vertical circular motion is given by $\sqrt{gr}$

Therefore, the minimum speed

$=\sqrt{10\times 4}$ m/s

$=2\sqrt{10}$ m/s

$=2\times 3.16$ m/s

$=6.32$ m/s

Obviously, the minimum speed does not depend upon the mass.

Hope this answer is helpful.