Q108 / 125 · BITSAT 2013 · Physics
An instantaneous displacement of a simple harmonic oscillator is $\mathrm{x}=\mathrm{A} \cos (\omega \mathrm{t}+\pi / 4) .$ Its speed will be maximum at time
- Correct answerA$\pi / 4 \omega$
- B$\pi / 2 \omega$
- C$\pi / \omega$
- D$2 \pi \omega$
Solution
Velocity, $\mathrm{v}=\frac{\mathrm{dx}}{\mathrm{dt}}=-\mathrm{A} \omega \sin (\omega \mathrm{t}+\pi / 4)$
Velocity will be maximum, when $\omega t+\pi / 4=\pi / 2$ or $\omega t=\pi / 2-\pi / 4=\pi / 4$
or $t=\pi / 4 \omega$
Hence, the correct answer is option: 'A'.