A ball with a mass of 3 kg3kg moving at 15 m/s15ms hits a still ball with a mass of 17 kg17kg. If the first ball stops moving, how fast is the second ball moving? How much kinetic energy was lost as heat in the collision?
2 Answers
The speed of the second ball is
The loss in kinetic energy is
Explanation:
We have conservation of momentum
So,
The kinetic energy, before the collision, is
The kinetic energy, after the collision, is
The loss in kinetis energy is
45/17\ "m"/"s"~~2.647\ "m"/"s"
4725/17~~277.941\ "J"
Explanation:
Remember that momentum
If two objects collide, their initial momentum and their final momentum are always the same, or
We substitute the values given to us in the question into this formula to get
To find the amount of kinetic energy lost, we find the initial kinetic energy minus the final kinetic energy. Kinetic energy can be found using the formula
The initial kinetic energy of the first and second ball is