Question

g= 10N/Kg

An engine does 1500 J of useful work with each 5000 J of energy supplied to it.

(a) What is its efficiency?

(b) What happened to the rest of the energy supplied.

Answer 1

$\huge{\dag} \: {\underline{\boxed{\sf{\purple{ Answer }}}}}$Given : For Carnot engine,

⇒T1=600K       T2=300K

⇒W=800J

We know,

Efficiency (n)=1−T1T2=QW

⇒QW=1−600300

⇒Q=1−21W

⇒21800

⇒Q=1600J

i.e, heat given to system is 1600J.

Hence, the answer is 1600.

Answer 2

Answer:

(a) 30%

(b) Thermal energy

Explanation:

(a) Efficiency = (Energy output / Energy input) x 100

= 1500/5000 x 100

= 30%

(b) The rest of energy supplied or wasted is 70%. This energy takes the form of thermal energy and is used to keep the air warm.