MCQ
A particle, moving with uniform speed $v$, changes its direction by angle $\theta$ in time $t$. Magnitude of its average acceleration during this time is
  • A
    zero
  • $\frac{2 v}{t} \sin \frac{\theta}{2}$
  • C
    $\frac{v \sqrt{2}}{t}$
  • D
    None of these

Answer

Correct option: B.
$\frac{2 v}{t} \sin \frac{\theta}{2}$
b
(b)

$a_{ av }=\left|\frac{\Delta v }{\Delta t}\right|=\frac{\left| v _f- v _i\right|}{t}$

$=\frac{\sqrt{v^2+v^2-2 v \cdot v \cdot \cos \theta}}{t}$

$=\frac{2 v}{t} \sin \frac{\theta}{2}$

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