A simple pendulum has a time period  T_{1}  when on the earth's surface and T_{2}  when taken to a height R above the earth's surface, where R is the radius of the earth. The value of  T_{2}/T_{1}  is  

A)    1         

B)  √2

C)   4         

D)   2

Answers (1)

@ vishal 

T=T=2\pi \sqrt{\frac{l}{g}}

g is inversly proportional to (R+h)^2 …..........h is height above the earth’s  surface

therefore T is proportional to R+h

\frac{T_{2}}{T_{1}}=\frac{R+h}{R}       ............ putting h=R

We get \frac{T_{2}}{T_{1}}=\frac{R+R}{R}=2