Work
If work gets done, then a transfer of energy takes place. If work is needed to be done, then a force is needed to be exerted. A displacement must also be present in the same direction as the force.
Work is the product of the force exerted and the displacement which took place due to the force being exerted. We can calculate work done using the formula:
Work done = Force × Distance moved in the direction of the force
Factors that affect work done are force and the displacement caused by the force.
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Force can either be a pull or a push.
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Force is said to be a vector quantity as it has magnitude along with the direction.
Examples:
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If you are pushing a car, you exert force.
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If you pull the rope connected to the tire, you are using your force to pull the tire.
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Displacement is the shortest distance between starting and ending positions.
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Displacement is also a vector quantity.
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For one-dimensional situations, displacement and distance are the same.
Examples of Work Done
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A boy is pushing a box with a force of 50 N. The box moves 1 meter due to the application of force.
Calculation:
Work done = 50 × 1 = 50 joules -
A boy is pushing a car with a force of 57 N. The car moves 3 meters due to the application of force.
Calculation:
Work done = 57 × 3 = 171 joules -
A boy is pulling a box connected to a rope with a force of 59 N. The box moves 6 meters due to the application of force.
Calculation:
Work done = 59 × 6 = 354 joules -
A bodybuilder lifts a mass of 20 kilograms to a height of 2 meters.
Calculation:
Work done = m × g × d = 20 × 10 × 2 = 400 joules -
A bodybuilder lifts a mass of 30 kilograms to a height of 3 meters.
Calculation:
Work done = m × g × d = 30 × 10 × 3 = 900 joules