One-Dimensional Elastic Collision · CAP 2017 #20

Physics · mechanics

Problem

Consider motion in only one dimension. An object with mass

m_1

and initial speed

v_{1,i}

in the direction of the positive x axis collides with a stationary object of mass

m_2

. The first object bounces back, moving with speed

v_{1,f}

in the direction of the negative x axis. The second object has a final speed

v_{2,f}

. If the collision was perfectly elastic, which of the following must be true? a)

m_1 = m_2

m_1 > m_2

c) Such a collision is impossible d)

m_1 < m_2

|v_{1,i}| < |v_{1,f}|