Efficiency Worksheet

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Efficiency Problems 1. The input work you do on a can opener is 24 J. The output work the can opener does is 18 J. What is the efficiency of the can opener?

2. A crane moved a 200 kg hot tub from the ground to the top of the hotel, 53 m above the ground. If the crane used 200,000 J of energy, how efficient was the crane?

3. What is the efficiency of a machine when the input is 263 J and the output is 142 J?

4. What is the output work when the efficiency is 62 % and the input is 39 J?

5. What is the input work when the output work is 2841 J and the efficiency is 15 %?

6. A front end loader moved a 100 kg pile of dirt from the ground to a ledge 1m above the ground. The machine used 1306 J of energy to perform this task. How efficient is the front end loader?