A body at 100°C is placed in contact with a body at 0°C. Heat flow stops when MCQ with Answer and Explanation

A body at 100°C is placed in contact with a body at 0°C. Heat flow stops when
A. Both reach 0°C
B. Heat content becomes equal
C. Thermal equilibrium is reached
D. Both reach 100°C
Answer: Option C
Solution (By JKSSB Mock Tests)
Heat flows until temperatures equal, i.e., thermal equilibrium. Not necessarily 50°C unless heat capacities equal.

Discuss this Question (0)

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

Practice More Physics Questions

Question #1
A flywheel rotates at 120 rpm. Angular velocity in rad/s is
A. π
B. 6π
C. 4π
D. 2π

Correct Answer: Option C


Explanation:
ω = 2π × (rpm/60) = 2π × 120/60 = 4π rad/s.

This question belongs to: Science Physics
Question #2
Which of the following is a non-ohmic conductor?
A. Iron wire
B. Diode
C. Copper wire
D. Silver wire

Correct Answer: Option B


Explanation:
Diode has non-linear I-V characteristic. Metals are ohmic.

This question belongs to: Science Physics
Question #3
Assertion (A): The coefficient of volume expansion of a solid is approximately three times its coefficient of linear expansion. Reason (R): Volume is a three-dimensional property derived from cubing the linear dimension.
A. Both A and R are true but R is NOT the correct explanation of A.
B. A is true but R is false.
C. A is false but R is true.
D. Both A and R are true and R is the correct explanation of A.

Correct Answer: Option D


Explanation:
The coefficient of linear expansion is alpha. A cube of side L has volume V = L^3. When heated, the new length is L(1+alphadT). The new volume is [L(1+alphadT)]^3. Expanding via binomial theorem and ignoring higher-order small terms gives V' = V(1 + 3alphadT). Thus, the volume expansion coefficient gamma is equal to 3alpha. Reason R correctly explains Assertion A.

This question belongs to: Science Physics