Question

a 50 kg boy runs and jumps with a forward velocity of 1.5 m/s into a 125 kg stationary boat. what is the final velocity of the boy/boat system? 0.43 m/s, forward 0.43 m/s, backward 1.1 m/s, forward 1.1 m/s, backward

Explanation:

Step1: Apply conservation of momentum

$m_1v_1=(m_1 + m_2)v_f$
$50\times1.5=(50 + 125)v_f$

Step2: Solve for $v_f$

$v_f=\frac{50\times1.5}{50 + 125}=\frac{75}{175}\approx0.43$ m/s, forward

Answer:

0.43 m/s, forward