MCQ
Ball $A$ moving at $12\ m/s$ collides elastically with $B$ as shown. If both balls have the same mass, what is the final velocity of ball $A$ ? ................$m/s$
- A$3$
- ✓$6$
- C$9$
- D$12$
✓
Answer
Correct option: B.
$6$
b
$\mathrm{mv}_{\mathrm{A}} \cos \theta=\mathrm{mv}^{\prime}_{\mathrm{Ay}}$
$\mathrm{mv}_{\mathrm{A}} \cos \theta=\mathrm{mv}^{\prime}_{\mathrm{Ay}}$
$\mathrm{mv}_{\mathrm{A}} \sin \theta=\mathrm{mv}_{\mathrm{Bx}}^{\prime}$
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