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Energy, Work, and Power. Some Definitions. Work= Force X Distance. If a person exerts 20 Newtons of force to move 5 meters, he has done 100 Joules of work. W= 20N X 5m = 100 J. Solve this Problem: A ball weighing three Newtons falls a distance of 4 meters. What work has been done?.
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Work= Force X Distance If a person exerts 20 Newtons of force to move 5 meters, he has done 100 Joules of work. W= 20N X 5m = 100 J
Solve this Problem: A ball weighing three Newtons falls a distance of 4 meters. What work has been done?
Let's Practice! Tap the ball to reveal the assignment
Mechanical Advantage and Mechanical Efficiency Both ratios (fractions and percentages) show us how well the machine works.
Mechanical Efficiency--How well the machine uses the energy you put into it. It compares the work you do to the machine and the work you get out. The work you get out of the machine is always less than the work you put in and you lose some energy to friction. ME= work output work input X 100
Mechanical Advantage--How much force you get out of the machine. Your mechanical advantage should be greater than 1 for the machine to be useful. MA = Force output Force input
Attachments Practice Problems on Work.docx