boxcar

[logistic_guy]

A \(\displaystyle 9700\)-\(\displaystyle \text{kg}\) boxcar traveling \(\displaystyle 18 \ \text{m/s}\) strikes a second car. The two stick together and move off with a speed of \(\displaystyle 4.0 \ \text{m/s}\). What is the mass of the second car?

 

[khansaheb]

A \(\displaystyle 9700\)-\(\displaystyle \text{kg}\) boxcar traveling \(\displaystyle 18 \ \text{m/s}\) strikes a second car. The two stick together and move off with a speed of \(\displaystyle 4.0 \ \text{m/s}\). What is the mass of the second car?

Please show us what you have tried and exactly where you are stuck.

Please follow the rules of posting in this forum, as enunciated at:

READ BEFORE POSTING​

Please share your work/thoughts about this problem

 

[logistic_guy]

A \(\displaystyle 9700\)-\(\displaystyle \text{kg}\) boxcar traveling \(\displaystyle 18 \ \text{m/s}\) strikes a second car. The two stick together and move off with a speed of \(\displaystyle 4.0 \ \text{m/s}\). What is the mass of the second car?

We solve this problem by the conservation of momentum equation.

\(\displaystyle m_1v_1 + m_2v_2 = (m_1 + m_2)v\)

We will plug in numbers assuming that the second car is not moving at the instant of the strike.

\(\displaystyle 9700(18) + 0 = (9700 + m_2)4\)

This gives:

\(\displaystyle m_2 = \textcolor{blue}{33950 \ \text{kg}}\)