A marksman standing on a motionless railroad car fires a gun into the air at an angle of 30.0° from the horizontal (the figure below). The bullet has a speed of 175 m/s (relative to the ground) and a mass of 0.0110 kg. The man and car move to the left at a speed of 1.20 10−3 m/s after he shoots. What is the mass of the man and car?(adsbygoogle = window.adsbygoogle || []).push({});

[Hint: A component of a system's momentum along an axis is conserved if the net external force acting on the system has no component along that axis.]

I know that Pi = Pf where there is conservation of momentum.

so M1V1i + M2V2i = M1V1f + M2V2f

0 = M1V1f + M2V2f

but I'm not sure what numbers to plug in because there is also an angle involved.

**Physics Forums | Science Articles, Homework Help, Discussion**

Join Physics Forums Today!

The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

# Homework Help: Marksman on a railroad car

**Physics Forums | Science Articles, Homework Help, Discussion**