The velocity of B after elastic collision is 3.45m/s
This type of collision is an elastic collision and we can use a formula to solve this problem.
[tex]v_2 = \frac{2m_1u_1}{m_1+m_2} - \frac{m_1 - m_2}{m_1 + m_2}u_2[/tex]
The data given are;
Let's substitute the values into the equation.
[tex]v_1 = \frac{2*281*2.82}{281+209} -\frac{281-209}{281+209}(-1.72)\\v_1 = 3.45m/s[/tex]
From the calculation above, the final velocity of the car B after elastic collision is 3.45m/s.
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