As shown in the figure a body of mass m moving vertically with speed 3 m / s hits a smooth fixed inclined…

As shown in the figure a body of mass $\mathrm{m}$ moving vertically with speed $3 \mathrm{m}/\mathrm{s}$ hits a smooth fixed inclined plane and rebounds with a velocity ${\mathrm{v}}_{\mathrm{f}}$ in the horizontal direction. If angle of incline is ${30}^{°}$, the velocity  ${\mathrm{v}}_{\mathrm{f}}$ will be

1. 3 m/s
2. $\sqrt{3}\text{ m/s}$
3. $1/\sqrt{3}\text{ m/s}$
4. This is not possible

Solution

Velocity along surface remain same

$3\text{sin }30^{\text{o}}={\text{v}}_{\text{f}}\text{sin }60^{\text{o}}$

$3\times \frac{1}{2}={\text{v}}_{\text{f}}\times \frac{\sqrt{3}}{2}$

${\text{v}}_{\text{f}}=\sqrt{3}\text{ m/s}$

Asked in: Practice

Practice more Center of Mass Momentum and Collision questions on Aicharya