Question

An elevator is accelerating down at 2 m/s2 in which a simple pendulum is suspended on one of its vertical wall with string length 2m. The string is pulled aside and bob is
held horizontally with string tight. The minimum downward speed (in m/s) with which bob is to be thrown so that bob completes the vertical circle is given by 4k. Then
value of k is:​

Answer 1

Answer:

Tension not only provides the centripetal force necessary for circular motion but also balances the component of weight along the string.

component of weight along the string is mgcosθ.

Thus, T−mgcosθ=

L

mv

2

⇒T=mgcosθ+

L

mv

2

.

solution