Work Energy And Power Question 142
Question: A particle is moving in the vertical plane. It is attached at one end of a string of length $ \lambda $ whose other end is fixed. The velocity at the lowest point is $ u $ . The tension in the string is $ \vec{T} $ and velocity of the particle is $ \vec{v} $ at any position. Then, which of the following quantity will remain constant.
Options:
A) $ \vec{T}.\vec{v} $
B) kinetic energy
C) Gravitational potential energy
D) $ \vec{T}\times \vec{v} $
Show Answer
Answer:
Correct Answer: A
Solution:
[a] The tension vector $ \overrightarrow{T} $ is always normal to velocity vector.
Hence $ \overrightarrow{T}.\vec{V} $ is always zero.
$ \Rightarrow $ (1) is correct choice.
