Given below are two statements: one is labelled as Assertion (A) and the other is labelled as Reason (R).
Assertion (A): When a pendulum is taken to the Moon, its time period will decrease.
Reason (R): On the Moon, the value of the acceleration due to gravity 'g' increases, which in turn decreases the time period of the pendulum.
In the light of the above statements, choose the most appropriate answer from the options given below:
- ABoth (A) and (R) are correct and (R) is the correct explanation of (A)
- B(A) is correct but (R) is incorrect
- C(A) is incorrect but (R) is correct
- DNone of the above is correct
Show answer and explanation
Correct answer: (d) None of the above is correct
Explanation
Both statements are wrong.
The time period of a simple pendulum is T = 2π√(l/g). On the Moon, the acceleration due to gravity is about one-sixth of its value on Earth:
- (A) is false: with a smaller g, the time period increases. The pendulum swings more slowly.
- (R) is false: g on the Moon decreases, it does not increase. Also, g is the acceleration due to gravity, not the gravitational constant (G), which is the same everywhere.