MCQ
A simple pendulum has time period $T$. The bob is given negative charge and surface below it is given positive charge. The new time period will be
- ✓Less than $T$
- BGreater than $T$
- CEqual to $T$
- DInfinite
✓
Answer
Correct option: A.
Less than $T$
a
(a) In this case time period of pendulum becomes
$T' = 2\pi \sqrt {\frac{l}{{\left( {g + \frac{{qE}}{m}} \right)}}} $
==> $T' < T$
(a) In this case time period of pendulum becomes
$T' = 2\pi \sqrt {\frac{l}{{\left( {g + \frac{{qE}}{m}} \right)}}} $
==> $T' < T$
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