Heat Transfer in Nature

What is the main message of the chapter "Heat Transfer in Nature"?

1. Heat moves only through metals.
2. Heat is transferred by conduction, convection, and radiation, and these processes explain many natural and everyday phenomena.
3. Heat and temperature are exactly the same.
4. Only the Sun produces heat.

Which statement about heat transfer is correct?

1. Heat always flows from colder objects to hotter objects.
2. Heat flows naturally from hotter objects to colder objects.
3. Heat remains fixed inside objects.
4. Heat can only travel through solids.

Why does hot air rise upward?

1. It becomes heavier.
2. It becomes less dense than cold air.
3. It loses all its particles.
4. It becomes a solid.

Which instrument is used to measure temperature?

1. Barometer
2. Thermometer
3. Hygrometer
4. Stopwatch

Which colour is best for keeping cool during summer?

1. Black
2. Dark blue
3. White
4. Brown

Why do dark-coloured clothes feel warmer in sunlight?

1. They reflect most heat.
2. They absorb more radiant heat.
3. They produce heat themselves.
4. They reduce sunlight.

Which natural phenomenon is caused by convection?

1. Reflection of light
2. Sea breeze
3. Formation of shadows
4. Magnetism

Why are cooking utensil handles often made of plastic or wood?

1. They are good conductors of heat.
2. They are poor conductors of heat.
3. They produce heat.
4. They increase cooking speed.

Why does the handle of a metal spoon become hot when placed in hot tea?

1. Due to convection
2. Due to radiation
3. Due to conduction
4. Due to evaporation

Which mode of heat transfer does not require a material medium?

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

Which mode of heat transfer occurs in liquids and gases?

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

Which material is a good conductor of heat?

1. Wood
2. Plastic
3. Copper
4. Rubber

Which mode of heat transfer mainly occurs in solids?

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

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

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

What is heat?

1. A type of matter
2. A form of energy that flows from a hotter object to a colder object
3. A type of gas
4. A kind of force