Explanation:
Given that,
Mass of the hockey puck, m₁ = 0.45 kg
Initial peed of the hockey puck, u₁ = 5.25 m/s (east)
Mass of other puck, m₁ = 0.85 kg
Initial speed of other puck, u₂ = 0 (at rest)
Let v₁ and v₂ are the final speeds of both pucks after the collision respectively. Using the conservation of momentum as :
[tex]m_1u_1+m_2u_2=m_1v_1+m_2v_2\\\\m_1v_1+m_2v_2=0.45\times 5.25+0.85\times 0\\\\m_1v_1+m_2v_2=2.36\\\\0.45v_1+0.85v_2=2.36.........(1)[/tex]
The coefficient of restitution for elastic collision is equal to 1.
[tex]C=\dfrac{v_2-v_1}{u_1-u_2}\\\\1=\dfrac{v_2-v_1}{u_1-u_2}\\\\1=\dfrac{v_2-v_1}{5.25-0}\\\\v_2-v_1=5.25.......(2)[/tex]
On solving equation (1) and (2) we get :
[tex]v_1=-1.611\ m/s\\\\v_2=3.63 m/s[/tex]
Hence, this is the required solution.
