Question

A light string of length 20cm is carrying a bob of mass 100 gm. It is pulled through an angle 60° and
released. Its maximum velocity is,
1) 1 m/s
2) 2 m/s
3) 1.4 m/s
4) 3 m/s​

Answer 1

Answer:

1.4m/sec

Explanation:

It's

As it's given clearly that length of string is twenty centimeters.

Hence 20cm is 0.2m. As we have to consider metres.

The weight of the Bob given is

As we will consider kgs then 100g = 0.1 kg.

Vertical height gain at 60 degrees from vertical will result in vertical component as = 0.2 -( cos 60 x 0.2 ) = 0.1 metre.

Potential energy or PE will be = (mgh) = (0.1 x 9.8 x 0.1) = 0.098 Joule.

This has to be converted to Kinetic energy at the vertical position.

Max. V = sqrt. (2KE /m ) = 1.4m/sec.

Answer 2

Answer:

hope it helps you friend