Question

1. Fill in the blanks.
(a) The
takes place due to the actual
movement of the heated particles within a
fluid.
(b) Heat cannot be transferred due to convection
in
(C) Due to convection, the hot particles move
while the cold particles move
(d) During the day, the land is heated
than ocean water.
(e) Movement of air from land towards ocean at
night is called​

Answer 1

e) Land breeze

I HOPE ITS HELP YOU

Answer 2

Answer:

(a) solid only

In conduction, the molecules vibrate and hit each other to transfer the heat energy between them. The molecules need not to travel from one end to other. Therefore, it is only possible in solids in which the molecules do not move but vibrate on heating.

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Question 2:

In which method of transfer of heat do the molecules travel from the hot the cold protion?

(a) conduction

(b) convection

(c) radiation

(d) all of the above

ANSWER:

(b) Convection

In the convection method, molecules travel from the hotter region to the colder region. The case is the same when water is heated.

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Question 3:

Handles of cooking utensils should be made of a material that

(a) conducts heat well

(b) does not conduct heat well

(c) radiates heat well

(d) does not radiate heat well

ANSWER:

(b) does not conduct heat well

Because, if handles conduct heat from the utensils, they will become too hot and make it impossible for us to hold the utensils.

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Question 4:

Convection occurs in

(a) solids only

(b) liquids only

(c) gases only

(d) liquids and gases only

ANSWER:

(d) liquids and gases only

In the process of convection, molecules move from a hotter place to a colder region. Therefore, convection is impossible in solids because the molecules are rigid and vibrate when heated. In liquids and gases, molecules are comparatively less rigid and can move easily, thereby making convection possible in them.

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Question 1:

What conditions are necessary for transfer of heat from one body to another by conduction?

ANSWER:

Conditions necessary for the transfer of heat from one body to the other through conduction are as follows:

The two objects must be in contact with each other.

The temperatures of both the objects must be different.

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Question 2:

Differentiate between good and bad conductors of heat.