MCQ
If a particle is moving on a circular path with constant speed, then the angle between the direction of acceleration and its position vector w.r.t. centre of circle will be ............ 
  • $\pi$
  • B
    $\frac{\pi}{2}$
  • C
    Zero
  • D
    $2 \pi$

Answer

Correct option: A.
$\pi$
a
(a)

Direction of Velocity is tangential to the circular path at any instance. At the very same instance, acceleration is along the radius, directed towards centre. So the angle between the direction of acceleration and its position vector with respect to the centre of the circle will be $\pi$ or $180^{\circ}$.

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