Flow of Heat

Q.

What is thermal equilibrium

Q.

How does heat energy transferred through conduction

Q.

Which of the following is not a mode of heat transfer?

1. Convection

2. Conduction

3. Radiation

4. Reflection

Q. Why do most stainless steel pans have copper bottoms?

1. Copper is a worse conductor of heat than steel.
2. Copper is a better conductor of heat than steel.
3. Copper is cheaper than steel.
4. Copper bottom makes the pan more durable.

Q.

Why are steel utensils provided with copper base ?

Q.

How does a thermos flask minimise heat transfer?

Q.

Explain zeroth law of thermodynamics

Q.

Describe the factors on which the amount of radiation absorbed by an object depends.

Q.

State the zeroth law of thermodynamics.

Q.

Heat and temperature are two very different things but they are very closely related to each other. Discuss how.

Q.

The process of heat transfer in which heat is transferred with the actual migration of medium particles is known as

Q.

How are heat and temperature related?

Q.

In daytime, how does the cold air in sea flow to land side?

Q.

(i) What is the normal temperature of a human body?

(ii) How does the heat from the sun reach us? [2 MARKS]

Q. Wind currents are generated due to on Earth.

1. uneven heating
2. even heating
3. motion of objects

Q. Rooms are fitted with ventilators to let the hot air out. What is the phenomenon involved here?

1. Conduction
2. Convection
3. Radiation
4. Insulation

Q. Convection in air happens when _____ air rises up and the ____ air from surrounding areas rushes to fill in its place.

1. hot, cold
2. cold, hot
3. hot, hot

Q. Which of the following happens in case of a sea breeze?

1. Cold air flows from sea to land during the night.
2. Cold air flows from land to sea during the day.
3. Cold air flows from sea to land during the day.
4. Cold air flows from land to sea during the night.

Q. Two bodies A and B are brought in contact with each other, and heat flows from A to B. Which of the following statements is true?

1. A is hotter than B.
2. B is hotter than A.
3. Both A and B are at the same temperature.
4. Both A and B would lose heat.

Q. During conduction, heat always flows from the hotter end to the colder end of an object.

1. True
2. False

Q. Insulators allow heat to flow through them more easily than conductors.

1. True
2. False

Q. Discuss the major cause of winds.

Q. How does heat transfer take place in vacuum? Give one example where heat is transferred in vacuum.

Q. What are conductors and insulators of heat? Explain with examples.

Q.

Transfer of heat through vacuum occurs by ________.

Q.

How does a conductor of heat differ from an insulator? Give examples for each.

Q.

Suppose you have three bodies A, B and C. When A and B are brought in contact, no heat flows between them. Now when B and C are brought in contact, heat flows from B to C until flow of heat stops. What will happen when A and C are brought in contact?

Q.

How does the conduction of heat occur?

Q.

We know that heat transfers but coldness (absence of heat) does not. Still when we take an ice cube in any 1 of our hands and bring the other hand near it feels cold. Why does this happen?🤔🤔🤔

Q.

Question 2

A beggar wrapped himself with a few layers of newspaper on a cold winter night. This helped him to keep himself warm because:

(a) Friction between the layers of newspaper produces heat

(b) Air trapped between the layers of newspaper is a bad conductor of heat.

(c) Newspaper is a conductor of heat.

(d) Newspaper is at a higher temperature than the temperature of the surrounding.