Q. Statement I Three pendulums are suspended from ceiling as shown in Fig. These three pendulums are set to oscillate as shon by arrows, and it is found that all three have same time period. Noe, all three are taken to a place where acceleration due to gravity changes to 4/9th of its value at the first place. If spring pendulum makes 60 cycles in a given time at this place, then torsion pendulum and simple pendulum will also make 60 oscillation in same (given) time interval. Statement II: Time period of torsion pendulum is independent of acceleration due to gravity.

Options

A. Statement I is true statement II is true, Statement II is a correct explanation for Statement I.
B. Statement I is true statement II is true, Statement II is NOT a correct explanation for Statement I.
C. Statement I is true, Statement II is false
D. Statement I is false, Statement II is true

Answer

D

Explanation

The period of the spring pendulum is `T=2pisqrt((m)/(k))`, Where k is the force constant,
Time period of the simple pudulum is `T=2pisqrt((l)/(k))`, where k is the torsion constan. If frequencies of all three are same at one place, then at some other place frequency of torsional and spring pendulums would be same and that of simple pendulum may differ (depending upon g).
So, Statement I is wrong and Statements II is correct.