Question

The velocity $v$ of a particle moving along a straight line and its distance $s$ from a fixed point on the line are related by $v^2=a^2+s^2$, then its acceleration equals

• A. $as$
• B. $s$
• C. $s^2$
• D. $2s$

Answer 1

The correct option is B $s$

$v^2=a^2+s^2$
$\Rightarrow 2v\frac{dv}{dt}=2s\frac{ds}{dt}$
$\Rightarrow 2va-2sv=0$
$\Rightarrow 2v(a-s)=0$
$\Rightarrow a=s$