Two spheres A and B of masses  respectively collide. A is at rest initially and B is moving with velocity v along x-axis. After collision B has a velocity $\frac{v}{2}$ in a direction perpendicular to the original direction.The mass A moves after collision in the direction

(a)same as that of B

(b)opposite to that of B

(c)

(d)

Concept Videos :-

#4 | Definition of Momentum
#5 | Conservation of Momentum
#6 | Problems

Concept Questions :-

Linear momentum

Here,${P}_{i}={m}_{2}vi+{m}_{2}×0$

${P}_{f}={m}_{2}\frac{v}{2}j+{m}_{1}×{v}_{2}$

Law of conservation of momentum

${P}_{i}={P}_{f}$

${v}_{2}=\frac{{m}_{2}}{{m}_{1}}vi-\frac{{m}_{2}}{{m}_{1}}\frac{v}{2}j$

From this equation we can find

$\mathrm{tan}\theta =-\frac{1}{2}$

$\theta ={\mathrm{tan}}^{-1}\left(-\frac{1}{2}\right)$to the x-axis.

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