Question

a large blue marble of mass 3.5 g is moving to the right with a velocity of 15 cm/s. the large marble hits a small red marble of mass 1.2 g that is moving to the right with a velocity of 3.5 cm/s. after the collision, the blue marble moves to the right with a velocity of 5.5 cm/s. what is the magnitude of the final velocity of the red marble? 9.2 cm/s 14 cm/s 24 cm/s 31 cm/s

Explanation:

Step1: Apply conservation of momentum

$m_1u_1 + m_2u_2=m_1v_1 + m_2v_2$

Step2: Substitute values

$3.5\times15+1.2\times3.5 = 3.5\times5.5+1.2\times v_2$

Step3: Solve for $v_2$

$v_2=\frac{3.5\times15 + 1.2\times3.5-3.5\times5.5}{1.2}=31$ cm/s

Answer:

31 cm/s