Easy INTEGER +4 / -1 PYQ · JEE Mains 2021

A particle executes simple harmonic motion represented by displacement function as

x(t) = A sin($\omega$t + $\phi$)

If the position and velocity of the particle at t = 0 s are 2 cm and 2$\omega$ cm s$-$1 respectively, then its amplitude is $x\sqrt 2$ cm where the value of x is _________________.

Answer (integer) 2

Solution

x(t) = A sin($\omega$t + $\phi$)<br><br>v(t) = A$\omega$ cos ($\omega$t + $\phi$)<br><br>2 = A sin$\phi$ ...... (1)<br><br>2$\omega$ = A$\omega$ cos$\phi$ ....... (2)<br><br>From (1) and (2)<br><br>tan$\phi$ = 1<br><br>$\phi$ = 45$^\circ$<br><br>Putting value of $\phi$ in equation (1),<br><br>$2 = A\left\{ {{1 \over {\sqrt 2 }}} \right\}$<br><br>$A = 2\sqrt 2$<br><br>$\therefore$ x = 2

About this question

Subject: Physics · Chapter: Oscillations · Topic: Simple Harmonic Motion

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