Q136 / 170 · Manipal (MET) 2020 · Physics
A mass $m$ hanging from a spring is doing simple harmonic motion with frequency $f$. If the mass is increased by 4 times, then frequency will be
- A$2 f$
- Correct answerB$f / 2$
- C$4 f$
- D$f / 4$
Solution
Frequency for a mass $m$ executing SHM
$f=\frac{1}{2 \pi} \sqrt{\frac{k}{m}}$ ....(i)
When the mass is increased by 4 times, then the new frequency
$f^{\prime}=\frac{1}{2 \pi} \sqrt{\frac{k}{4 m}}=\frac{1}{2} \cdot \frac{1}{2 \pi} \sqrt{\frac{k}{m}}=\frac{f}{2}$
Hence, the correct answer is option: 'B'.