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A particle is moving in a straight line under the action of a force of 685 dynes acting in the direction of motion.
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Find the work π€ in ergs done by the force over a displacement of 390 centimeters.
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Take the acceleration due to gravity π to be equal to 9.8 meters per square second.
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We recall that work is the measure of energy transfer when a force πΉ moves an object through a distance π.
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The formula we use is work done is equal to force multiplied by distance.
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We do need to be a little bit careful with the units we use though.
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Work done is often measured in joules.
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This corresponds to a force measured in newtons and a distance measured in meters.
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Sometimes though, we might choose to measure the work done in ergs.
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This corresponds to a force measured in dynes and a distance measured in centimeters.
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Note, though, weβre looking to calculate the work in ergs and we have the force in dynes and the displacement or distance in centimeters.
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And so we can simply apply the formula π€ equals 685 times 390.
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That gives us 267150 ergs or 267000 ergs, correct to three significant figures.
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We might then choose to write this in standard index form.
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Work done is 2.67 times 10 to the fifth power ergs.