Heat and Thermodynamics MCQ question and answer with solution

41

Assertion (A) The boiling point of water decreases as the altitude increases.
Reason (R) The atmospheric pressure increases with altitude.

A) Both A and R are true, and R is the correct explanation of A B) Both A and R are true, but R is not the correct explanation of A C) A is true, but R is false D) A is false, but R is true

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Answer & Solution

Answer: Option C

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42

Which one of the following statements is not correct?

A) In the conduction mode of transference of heat, the molecules of solid pass heat from one molecule to another without moving from their positions B) The amount of heat required to raise the temperature of a substance is called its specific heat capacity C) The process of heat transfer in liquids and gases is through convectionmode D) The process of heat transfer from a body at higher temperature to a body at lower temperature without heating the space between them is known as radiation

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Answer & Solution

Answer: Option B

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43

When red glass is heated in dark room it will seem

A) green B) purple C) black D) yellow

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Answer & Solution

Answer: Option A

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44

Water evaporates-

A) At freezing point B) At the attached temperature C) At all temperatures D) At the boiling point

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Answer & Solution

Answer: Option C

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45

The hand bums more by steam comparatively to boiling water, because

A) The steam has latent heat B) Steam sneaked into the body C) The steam has more power D) Steam is gig

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Answer & Solution

Answer: Option A

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46

What changes will happen to a bowl of ice and water kept at exactly 0°C?

A) All ice will melt B) All water will become ice C) No change will happen D) Only some ice will melt

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Answer & Solution

Answer: Option C

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47

Due to presence of . . . . . . . . in an object, it conducts electricity.

A) Positron B) Proton C) Electron D) Neutron

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Answer & Solution

Answer: Option C

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48

The blackboard seems black because it

A) reflects every colour B) does not reflect any colour C) absorbs black colour D) reflects black colour

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Answer & Solution

Answer: Option B

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49

What is the measure of room temperature on the Kelvin scale?

A) 98 K B) 298 K C) 273 K D) 373 K

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Answer & Solution

Answer: Option B

Solution:

The correct answer is B: 298 K.
Here's why:
Room temperature is generally considered to be around 25 degrees Celsius (°C).
The Kelvin scale is related to the Celsius scale by a simple formula: Kelvin (K) = Celsius (°C) + 273.15.
So, to convert 25°C to Kelvin, we add 273.15 to 25, which gives us approximately 298.15 K.
Therefore, 298 K is the closest and most accurate representation of room temperature on the Kelvin scale.
The other options are incorrect:
98 K is extremely cold.
273 K is the freezing point of water (0°C).
373 K is the boiling point of water (100°C).

50

The silvering in thermo flask is done to avoid heat transfer by

A) convection B) conduction C) Both A and B D) radiation

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Answer & Solution

Answer: Option D

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Heat and Thermodynamics MCQ question and answer with solution | Physics Gk MCQs