How Efficient Are Human Leg Muscles?

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The discussion focuses on calculating the efficiency of human leg muscles based on energy output and input. A participant calculated output energy using a specific formula but arrived at a different value than expected, questioning their method. Another contributor clarified that the input energy includes both work and heat, emphasizing the importance of considering heat generated by muscles. The conversation highlights the need for accurate data on heat production to determine efficiency correctly. Overall, the discussion underscores the complexities involved in measuring muscle efficiency.
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Please refer to the image attached.

For Q5, I did it like this:

Output energy = (50kg x 10 x 0.35metre) x 30times x 4minutes

And divide the answer by 120kJ.

The percentage I got is 17.5 Joules but the answer is 15J.

Did I do anything wrong?

For Q6, the temperature should fall, correct?

Thanks in advance.
 

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The muscles did work and produced heat. So the input energy is work+heat. The efficiency is output energy divided by input energy.

ehild
 
But there are no informations about heat.
 
coconut62 said:
But there are no informations about heat.

Read the problem text: "The muscles generate 120 kJ heat".

ehild
 

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