A simple pendulum is executing simple harmonic motion with a time period T. If the length of the pendulum is increased by 21%, the percentage increase in the time period of the pendulum of is

Options

A. 0.1
B. 0.21
C. 0.3
D. 0.5

Answer

A

Explanation

`T=2pisqrt((l)/(g)) implies (T_(1))/(T_(2))=sqrt((l_(1))/(l_(2)))`
`implies (T_(1))/(T_(2))=sqrt((100)/(121)) implies T_(2)=1.1 T_(1)`
% increase`=(T_(2)-T_(1))/(T_(1)) xx100=10%`.