Question

A hollow sphere has radius 6.4 m. what is the minimum velocity required by a motor

cyclist at bottom to complete the circle. (Ans: V=17.7 m/s )​

Answer 1

Explanation:

To complete the circle,

R

mv

0

2

=mg⇒v

0

2

=gR

Now, from conservation of energy:

K

1

+∪

1

=K

2

+∪

2

2

1

mv

2

+0=

2

1

mv

0

2

+mg(2R)

⇒v

2

=gR+4gR⇒v=

5gR

⇒v=

5×10×6.4

=17.7m/s

solution