Unit Summary

Unit Symbol Description
joules J base unit
kilojoules kJ 1,000 J = 1 kJ
megajoules MJ 1,000,000 J = 1 MJ
gigajoules GJ 1,J = 1 GJ

## What is the relationship between joules and calories?

The calorie was originally defined as the amount of heat required at a pressure of 1 standard atmosphere to raise the temperature of 1 gram of water 1° Celsius. Since 1925 this calorie has been defined in terms of the joule, the definition since 1948 being that one calorie is equal to approximately 4.2 joules.

## What is the difference between joules and kilojoules?

1 Joule (J) is equal to 0.001 kilojoule (kJ). To convert joules to kilojoules, multiply the joule value by 0.001 or divide by 1000. For example, to convert 100 J to kJ, divide 100 by 1000, that makes 0.1 kJ is 100 J.

0.46 celsius

## What is the energy equivalent of an object with a mass of 2.5 kg?

Answer: 2500g is the energy.

## What is the energy equivalent of an object with a mass of 4.1 kg?

The energy equivalent of an object with a mass of 4.1 kg is 3.7 × J. Explanation: One of the significant findings of Einstein is the mass energy equivalence. According to this law, the energy is equivalent to the product of mass and square of velocity of light.

## What evidence is there for the equivalence of mass and energy?

Mass-energy equivalence states that mass is concentrated energy. In his theory of special relativity Einstein formulated the equation E=mc^2. There is a tremendous amount of energy in mass. A 20g marble contains as much energy as a 500 kiloton hydrogen bomb, but this energy is very difficult to release.

## Which statement correctly describes the mass of an object?

The correct statement about the mass is: Mass is the amount of matter in an object. Volume is the amount of space taken up by an object.