Q91 / 125 · BITSAT 2017 · Physics

A body of mass $1 kg$ is executing simple harmonic motion. Its displacement $y (cm)$ at $t$ seconds is given by $y = 6 \sin (100 t + \frac{π}{4})$ . Its maximum kinetic energy is

Solution

Given, $a = 6 cm = 6 \times 10^{- 2} m$

$ω = 100 rad s^{- 1}, m = 1 kg$

$K_{\max} = \frac{1}{2} m ω^{2} a^{2}$

$= \frac{1}{2} \times 1 \times {(100)}^{2} \times {(6 \times 10^{- 2})}^{2}$

$= 18 J$

Hence, the correct answer is option: 'B'.