Entropy of the universe tends to be

Important Questions on Thermodynamics

MEDIUM

JEE Main

IMPORTANT

Physics Crash Course JEE Main>Chapter 10 - Thermodynamics>Level 1>Q 44

A heat engine operating between $40$ degrees $C$ and $380$ degrees $C$ has an efficiency $60\%$ of that of a Carnot engine operating between the same temperatures. If the engine absorbs heat at a rate of $60 kW$, at what rate does it exhaust heat (in $kW$ )? (Approximate the answer to the nearest integer.)

EASY

JEE Main

IMPORTANT

Physics Crash Course JEE Main>Chapter 10 - Thermodynamics>Level 1>Q 45

An ideal heat engine exhausting heat at $77°\mathrm{C}$ is to have a $30\%$ efficiency. Find the temperature$\left(\text{in} °\mathrm{C}\right)$ at which it must take heat.

MEDIUM

JEE Main

IMPORTANT

Physics Crash Course JEE Main>Chapter 10 - Thermodynamics>Level 1>Q 46

A Carnot engine operates between two reservoirs of temperatures $900 \mathrm{K}$ and $300 \mathrm{K}.$ The engine performs $1200 \mathrm{J}$ of work per cycle. The heat energy (in J) delivered by the engine to the low temperature reservoir, in a cycle, is

EASY

JEE Main

IMPORTANT

Physics Crash Course JEE Main>Chapter 10 - Thermodynamics>Level 1>Q 47

A Carnot engine has the same efficiency between (i) $100 \mathrm{K}$ and $500 \mathrm{K}$, (ii) $\mathrm{T} \mathrm{K}$ and $900 \mathrm{K}$. The value of $\mathrm{T}$ is

EASY

JEE Main

IMPORTANT

Physics Crash Course JEE Main>Chapter 10 - Thermodynamics>Level 1>Q 48

The coefficient of performance of a carnot refrigerator working between $30°\mathrm{C}$ and $0°\mathrm{C}$ is

EASY

JEE Main

IMPORTANT

Physics Crash Course JEE Main>Chapter 10 - Thermodynamics>Level 1>Q 49

The coefficient of performance of a refrigerator is $5$. If the inside temperature of freezer is $-20° \mathrm{C}$,  then the temperature of the surroundings to which it rejects heat is:

EASY

JEE Main

IMPORTANT

Physics Crash Course JEE Main>Chapter 10 - Thermodynamics>Level 1>Q 50

A carnot engine working between $27°\mathrm{C}$ and $127°\mathrm{C},$ draws $600 \mathrm{J}$ of heat from the reservoir in one cycle. The work done by the engine

EASY

JEE Main

IMPORTANT

Physics Crash Course JEE Main>Chapter 10 - Thermodynamics>Level 1>Q 51

A carnot engine having an efficiency of $\eta =\frac{1}{10}$ as heat engine, is used as a refrigerator. If the work done on the system is $10 \mathrm{J}$, the amount of energy absorbed from the reservoir at lower temperature is,