Question

Figure gives the $x-t$ plot of a particle executing one dimensional simple harmonic motion. Mark the correct combination. The signs of position, velocity and acceleration variables at

• A. $t=0.3\, s , x< 0, v < 0, a < 0$
• B. $t=1.2\, s , x > 0, v > 0, a >0$
• C. $t=-1.2\, s , x > 0, v > 0, a < 0$
• D. $t=-0.3\, s , x > 0, v < 0, a < 0$

Answer 1

Answer: (D)

Between $-0.5 < t < 0.5$, the graph has a negative slope.
$\Rightarrow \frac{d x}{d t}<0$ or $v < 0$
At $t=-0.3 \,s ,$ the slope becomes more and more negative, so
$\frac{d v}{d t} < 0$
or $a < 0 . x > 0$ is visible.