Question

A 9500 kg boxcar traveling at 14 m/s strikes a stationary second car. The two stick together and move off with a speed of 6.0 m/s. What is the mass of the second car?

Answer 1

Answer: The mass of the second car is 12666.7 kg

Explanation:

To calculate the mass of car, we use the equation of law of conservation of momentum, which is:

$m_1u_1+m_2u_2=(m_1+m_2)v$

where,

$m_1$ = mass of car 1 = 9500 kg

$u_1$ = Initial velocity of car 1 = 14 m/s

$m_2$ = mass of car 2 = ? kg

$u_2$ = Initial velocity of car 2 = 0 m/s

$v$ = Final velocity = 6.0 m/s

Putting values in above equation, we get:

$(9500\times 14)+(m_2\times 0)=(9500+m_2)6.0\\\\m_2=\frac{9500\times 14}{6}-9500=12666.7kg$

Hence, the mass of the second car is 12666.7 kg