Question

A particle of mass m moving towards the east with speed u collides with another particle of same mass and same speed v moving towards north. If two particles stick together, the new particle of mass 2m will have a speed of

• A. v
• B. $\frac{v}{2}$
• C. $\frac{v}{\sqrt{2}}$
• D. v√2

Answer 1

Answer: (C)

$\frac{v}{\sqrt{2}}$

Answer 2

2mv′ = $\sqrt{(mv)^{2} + (mv)^{2}} = mv\sqrt{2}$ ⇒ v′ = $\frac{v}{\sqrt{2}}$