The efficiency of a Carnot engine depends on: MCQ with Answer and Explanation

Question
The efficiency of a Carnot engine depends on:
A. Working substance
B. Temperatures of source and sink only
C. Size of the engine
D. Both (a) and (b)
Answer: Option B
Solution (By JKSSB Mock Tests)
Carnot efficiency η = 1 - T₂/T₁, depending solely on absolute temperatures of heat source (T₁) and sink (T₂). It is independent of working substance, engine size, or other details. This universality makes Carnot cycle the theoretical maximum efficiency benchmark. Memory tip: 'Carnot efficiency: only T_hot and T_cold matter; real engines have lower efficiency'. This thermodynamics concept is frequently tested in competitive exams. Always recall that Carnot efficiency is an ideal limit; real engines have additional losses reducing efficiency below this value.
This question belongs to: Science Physics
Request complete Subject PDF

Discuss this Question (0)

No comments yet. Be the first to start the discussion!

Practice More Physics Questions

Question #1
Which of the following colors of light has the lowest frequency?
A. Red
B. Green
C. Blue
D. Violet
Discuss
Get Complete Subject PDF for Science

Correct Answer: Option A

Explanation:
In the visible spectrum (VIBGYOR), wavelength increases from Violet to Red. Since speed = frequency × wavelength (c = fλ), frequency is inversely proportional to wavelength. Red light has the longest wavelength and therefore the lowest frequency and lowest energy. Violet has the shortest wavelength and highest frequency.
This question belongs to: Science Physics
Question #2
The time period of oscillation of a mass M attached to a spring of force constant k is:
A. 2π√(g/l)
B. 2π√(k/M)
C. 2π√(M/k)
D. π√(M/k)
Discuss
Get Complete Subject PDF for Science

Correct Answer: Option C

Explanation:
For spring-mass system undergoing SHM, time period T = 2π√(M/k), derived from F = -kx = Ma ⇒ a = -(k/M)x, so ω² = k/M, T=2π/ω=2π√(M/k). Option B has inverse ratio; C misses factor 2; D is for pendulum. Memory tip: 'Spring: T ∝ √(M/k); Pendulum: T ∝ √(l/g)'. This standard formula is frequently tested in oscillations sections of competitive exams. Always verify dimensions: √(kg / (N/m)) = √(kg·m/N) = √(s²) = s, correct for time period.
This question belongs to: Science Physics
Question #3
Which of the following is a vector?
A. Distance
B. Displacement
C. Energy
D. Speed
Discuss
Get Complete Subject PDF for Science

Correct Answer: Option B

Explanation:
Displacement has both magnitude and direction, vector. Distance is scalar (path length). Speed scalar. Energy scalar. Vector examples: velocity, force, acceleration.
This question belongs to: Science Physics
Explore All Physics MCQs
Today's Top Topics
Biology 2054 Physics 1287 chemistry 1089
Explore Subjects
Maths 5575 English 15164 Science 4430 Static General Knowledge 6362 Economy GK 2220
Practice Mix
Milk and water are in ratio 4:6 in a 273 L mixture. Quantity of milk?
The blaze ______ they doused was huge.
The 'Rani of Jhansi' is associated with:
The posters were ________ all over the city.
The principal that gives Rs. 453600 interest in 8 years at 9% SI is