Kinetic Energy Facts

Anytime some are in motion it is said to have kinetic energy.

This could be you when you are running down the street, a bicycle when it is moving or even the wind and water in the ocean. Kinetic energy also includes anything that has rotation or vibrates.

  • Whether an object increases speed or slows down, it always keeps the same amount of kinetic energy.
  • The word ‘kinetic’ comes from the Ancient Greek word ‘kinesis’, which translates to ‘motion’.

The well-known philosopher, Aristotle, studied the concept of kinetic energy, but credit is actually given to Lord Kelvin in England for coining the term in his 1849 research.

  • There are two types of kinetic energy: transitional and rotational.
  • Transitional kinetic energy depends on the motion through space. An example would be a pitcher throwing a baseball. The ball contains the kinetic energy contained from the pitcher throwing the ball.
  • Rotational kinetic energy depends on an object’s motion that is centered on an axis. An example of rotational kinetic energy would be the earth’s rotation.
  • If an object’s speed and mass is known, you can calculate the kinetic energy

Kinetic energy is measured in a unit called a ‘joule’. Another unit for configuring energy is known as the ‘newton’ (named after Isaac Newton) and is measured through the use of a newton-meter.

  • The more quickly an object is moving, the more kinetic energy the object will have.
  • When understanding kinetic energy, direction doesn’t matter. An object can be going left to right, right to left, up and down or down and up; or any type of direction.
  • An interesting thing about kinetic energy is that when the speed of an object doubles, the kinetic energy actually quadruples.
  • When the mass of any object doubles, the kinetic energy of that object also doubles.

When an object collides with another object, as in the case of a baseball bat hitting a ball, it will transfer its kinetic energy to the alternate object. The baseball bat transfers its kinetic energy to the ball and the ball then moves in a different direction, containing all of the kinetic energy.

Any object that is pulled in an uphill manner, such as a roller coaster car, will gain potential kinetic energy. Once it hits the top it has the most potential kinetic energy.

Then, it begins to move down the other side of the roller coaster and gains speed as well as kinetic energy. The funny thing is that going down is both gaining and losing potential energy as it had already achieved the most when it was at the top.

By the time the roller coaster car reaches the bottom, it has achieved most of its kinetic energy and also is at the point of the least potential energy.

  • For an object to gain or increase its kinetic energy, some form of work must be done to the object.
  • Most of the kinetic energy starts as a different type of energy and is then converted.

The more mass an object has, the more kinetic energy it will have. If two objects, such as a bicycle and a car, are going at the same speed, the car will have great kinetic energy because it has a greater mass.

An example of the reaction would be: which causes greater damage: the car or the bike, both going at the same speed and then hitting an object?