Kinetic energy: what is kinetic energy and formula

THE kinetic energy it is the work done by the bodies that generates their movement.

This name comes from the Greek “kinetics” which means “movement”.

The unit of measure is the Joule (j) in honor of the scientist James Prescott Joule who researched this phenomenon.

Kinetic energy formula

Ec = mv (2) squared/2

Ec = kinetic energy, which can also be shown by the letter K (J)

m = body mass (kg)

v = body velocity (m/s)

The conclusion is that if we double the mass of a body, with its velocity maintained, the kinetic energy of this body will double. But the speed is also squared.

So if the value doubles and the body mass remains constant, the kinetic energy will quadruple.

Example

THE kinetic energy of a 60 kg person who is moving at a speed of 10 m/s will be 3000 J.

Kinetic energy and work

In order to have a variation of speed in a body, work needs to be done on it. This varied body speed causes the Is it over there have variation.

Template exercises

1. A 1,200Kg car is traveling at a speed of 10m/s.
2. Determine the kinetic energy of a bird that has a mass of 150g and flies horizontally at a speed of 28.8 km/h.
3. An airplane that has a mass of 2000Kg moves horizontally at a height of 700m from the ground at a speed of 540Km/h.

Answers:

• Answer Question 1

m= 1,200
v = 10m/s (in the statement it is already in meters per second)
E= 1200. 102
2
E= 1200. 100
2
E = 60000 J

• Answer Question 2

m=150g
v= 28.8 km / h
E= m.v2 / 2
E=150. 28.8 / 2 (transforms into meters per second) 28.8: 3.6
E=150. 82 / 2
E=150. 64 / 2
E = 4,800 J

• Answer Question 3

m= 2000 kg (2 ton)
v= 540 km/h (transforms into meters per second) 540: 3.6
E= 2000.1502 / 2
E= 2000.22.500 / 2
E= 45,000,000 / 2
E= 22.5 million J

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See also: Electric energy is a form of energy based on the generation of electrical potential differences between two points, which allow the establishment of an electrical current between them, know more