Question

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?

Answer 1

`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 source`Q`.

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

Given, `W=836J`

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

Answer 2

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`

Answer 3

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