Answer:
150 joules of energy is expelled to the low temperature reservoir each minute.
Explanation:
Lets assign the terms first.
[tex]T_H ,T_L,Q_H,Q_L,W[/tex] where ...
[tex]T_H[/tex] = 750 K that is, the high temperature of the reservoir.
[tex]T_L[/tex] = 350 K, low temperature of the reservoir.
[tex]Q_H[/tex] = 400 J,energy extract from the reservoir.
[tex]W[/tex] = 250 J, work done.
[tex]Q_L[/tex] = energy expelled.
And
Formula to be used:
⇒ [tex]Q_H=W+Q_L[/tex]
Re-arranging.
⇒ [tex]Q_L=Q_H-W[/tex]
Now plugging the values of [tex]Q_H[/tex] and [tex]W[/tex].
⇒ [tex]Q_L=400-250[/tex]
⇒ [tex]Q_L=150[/tex] Joules
So energy expelled to the low temperature reservoir is of 150 joules.