A hunter holds a 3kg rifle and fires a bullet of mass 5g with a muzzle velocity of 300m/s. What is the final kinetic energy of the bullet and the riffle?

.005 (300) = - 3 v

v = -.5

Ke = (1/2)(.005)(300)^2 + (1/2)(3)(-.5)^2

224.625 J

To find the final kinetic energy of the bullet and rifle, we need to calculate the kinetic energy for each object separately.

The formula to calculate the kinetic energy is:
Kinetic Energy = (1/2) * Mass * Velocity^2

First, let's calculate the kinetic energy of the bullet:
Mass of the bullet = 5g = 0.005kg
Velocity of the bullet = 300m/s

Kinetic Energy of the bullet = (1/2) * 0.005kg * (300m/s)^2
= 0.5 * 0.005kg * 90000m^2/s^2
= 225J (Joules)

Now, let's calculate the kinetic energy of the rifle:
Mass of the rifle = 3kg
Velocity of the rifle = 0m/s (since the rifle is not moving after firing the bullet)

Kinetic Energy of the rifle = (1/2) * 3kg * (0m/s)^2
= 0J (Joules)

Therefore, the final kinetic energy of the bullet is 225 Joules, and the final kinetic energy of the rifle is 0 Joules.