Question

A 0.15 kg glider moving to its right with 0.8ms^-1 collide head on with another glider of mass 0.3 kg moving with a speed 2.2 ms^-1to left. Find the velocity of 0.15kg glider after collision. Assume collision is elastic.

• A. 2.2 ms^-1
• B. 3.2 ms^-1
• C. 2.96 ms^-1 to right
• D. 2.96 ms^-1 due left

Answer 1

Answer: (B)

3.2 ms^-1

Answer 2

v₁ = $\left( \frac{m_{1} - m_{2}}{m_{1} + m_{2}} \right)u_{1} + \frac{2m_{2}}{m_{1} + m_{2}}u_{2}$v₂

= $\frac{- 0.15}{0.45}(0.8) + \frac{2 \times 0.3}{0.45}( - 2.2)$ = -3.2 ms^-1