A heat engine with an efficiency of 17 % does 836 J of work in each cycle. How much heat must be supplied from the high-temperature source in each cycle?

3 Answers
Mar 16, 2018

4917.65J

Explanation:

Coefficient of efficiency of a heat engine is defined as the ratio of work done W by it to heat added from heat sourceQ.

So,we can write, 17/100=W/Q

Given, W=836J

So, Q=836*(100/17)=4917.65J

Mar 16, 2018

See below
4920J

Explanation:

Let's recall the definition of efficiency:
E= W_(out)/ W_("in")*100

So, we are given the output of work here as 836 J and the efficiency as 17%

Let's substitute and solve:
W_(out)/E*100= W_("in")
(836 J)/17*100 approx 4920 J

Mar 16, 2018

The total energy consumed per cycle is 4918 J

Explanation:

17 % efficiency means that in one cycle, "work done"/"total energy consumed" = 0.17

Therefore if 836 J of work is done in each cycle, solving the following equation for "total energy consumed" will provide the answer to this question.

(836 J)/"total energy consumed" = 0.17

"total energy consumed" = (836 J)/0.17 = 4918 J

I hope this helps,
Steve