Solved Examples on Unit of Energy
Example 1: Calculate the kinetic energy of a car traveling at a speed of 20 meters per second with a mass of 1000 kilograms.
Solution:
Given:
Mass = 1000 kg
Velocity = 20 m/s×
Kinetic Energy = 1/2mv2
= 1/2 × 1000 × (20)2
= 1/2 × 1000 × 400
= 2,00,000 joules
Example 2: Determine the potential energy of a book weighing 5 kilograms placed on a shelf 2 meters above the ground.
Solution:
Given
Mass = 5 kg
Height = 2 m
Acceleration due to gravity (g) = 9.8 m/s2
Potential Energy =mgh
= 5 × 9.8 × 2
= 98 joules
Example 3: Calculate the work done when a force of 50 newtons is applied to move a box a distance of 10 meters along the direction of the force.
Solution:
Force = 50 N
Distance = 10 m
Work Done = Force × Distance
= 50 × 10
= 500 joules
Unit of Energy
Unit of energy is a standard quantity used to measure the work done by a force or the amount of heat transferred. The SI unit of energy is the joule (J). Other Units of energy are electronvolt (eV), calorie, BTU, etc
In this article, we will define energy, discuss possible units to measure it, SI unit of energy, Conversion of energy unit, and some solved examples based on it.
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