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A crane lifts a body of mass 132 kilograms to a height of 20 metres.
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Find the increase in the body’s gravitational potential energy.
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Consider the acceleration due to gravity 𝑔 to be equal to 9.8 metres per square second.
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Remember, gravitational potential energy represents the potential an object has to do work as a result of being located at a particular position in a gravitational field.
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The formula we use for gravitational potential energy, which is measured in joules, is mass multiplied by acceleration due to gravity multiplied by height.
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In this question, the crane is lifting a body of mass 132 kilograms.
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We multiply this by acceleration due to gravity, which is 9.8.
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And the height of the object is 20 metres.
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We set the starting height of the object equal to zero.
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And so the increase in the body’s gravitational potential energy’s change will be 132 times 9.8 times 20, technically, minus zero, although of course we don’t need to subtract zero.
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132 multiplied by 9.8 multiplied by 20 is 25872.
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And so the increase in the body’s gravitational potential energy is 25872 joules.