Question

a stone of mass 1 kg is tied with a string and it is whirled in a vertical circle of radius 1 m. if tension at the highest point is 14 n, then velocity at lowest point will be (1) 3 m/s (2) 4 m/s (3) 6 m/s (4) 8 m/s​

Answer 1

Answer:

ANSWER

Mass of the stone, m=1Kg

Radius, r=1m

Tension, T=14N

Let v

1

​

is velocity at the top point and v

2

​

is at the bottom point.

The tension at the top point is:

T=

r

mv

1

2

​

​

−mg

14=

1

1v

1

2

​

​

−1×10

v

1

2

​

=4

v

1

​

=2

So, total kinetic energy at the bottom is:

2

1

​

mv

2

​

2

=(mgh)

bottom

​

+

2

1

​

mv

1

​

2

2

1

​

mv

2

​

2

=20+2

2

1

​

mv

2

​

2

=22

v

2

​

=

44

​

=6.63m/s

Explanation: