Question

One calorie of heat energy is equivalent to approximately ______ joules of mechanical energy.
1. 0.24
2. 4.2
3. 0.48
4. 2.4

Answer 1

Correct Answer - Option 2 : 4.2

The correct answer is 4.2.

• The ability to do work is called energy.
• Calorie and Joule both are units of energy.
• Joule is a derived unit of energy or amount of heat in the International System of Units and Calorie is a unit of energy.
• 1 Calorie = 4.184 Joules, which is approximately equal to 4.2 Joules.

• Other important units:

Quantity	Unit
Power	Watt (J/s)
Temperature	Kelvin (K)
luminous  Intensity	Candela (cd)
Electric Current	Ampere (A)