A 28 kg gun is standing on a frictionless sur-
face. The gun fires a 47.4 g bullet with a
muzzle velocity of 319 m/s.
The positive direction is that of the bullet.
Calculate the kinetic energy of the bullet im-
mediately after the gun was fired.
Answer in units of J

Question

A 28 kg gun is standing on a frictionless sur-
face. The gun fires a 47.4 g bullet with a
muzzle velocity of 319 m/s.
The positive direction is that of the bullet.
Calculate the kinetic energy of the bullet im-
mediately after the gun was fired.
Answer in units of J

anonymous · Answer

Calculate the kinetic energy of the gun imme-
diately after the gun was fired.
Answer in units of J

primeralph · Answer

Try.

anonymous · Answer

I did and I got it wrong

primeralph · Answer

What is KE?

anonymous · Answer

does the mass of the bullet have to be in kg?

primeralph · Answer

Yes. That's basic stuff.

anonymous · Answer

The momentum of the gun is negative but the KE can't be right?

primeralph · Answer

In this case, no, v^2 is always positive. .

anonymous · Answer

How do I find the kinetic energy of the gun though?