Answer: Option A. ->
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Effects: 1 Mark each
The effects of heat energy are the following:
(i) When heat is supplied to a body, its temperature rises.
(ii) When heat is supplied to a body it expands, i.e. its dimensions are changed. Material bodies expand on heating and contract on cooling.

Answer: Option A. ->
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Each part: 1 Mark
Three scales of temperature are Celsius scale, Kelvin scale, and Fahrenheit scale.
The Celcius scale is followed in India.
 

Answer: Option A. ->
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Conductor: 1 Mark
Insulator: 1 Mark
Conductors are those materials which allow heat to flow through them easily, the phenomenon is called conduction.
Conduction usually takes place in metals. Example copper, aluminum, etc.
Insulators are those materials which do not allow transfer of heat. For example wool, wood.

Answer: Option A. ->
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Each point: 1 Mark
Boiling:
1) It takes place througout the mass of the liquid.
2) It is a fast process.
3) It takes place at a fixed temperature for a particular liquid.
Evaporation:
1) It takes place only at the surface of liquids.
2) It is a slow process.
3) It takes place at all temperatures.

Answer: Option A. ->
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Explanation: 2 Marks
Mode: 1 Mark
When we light a candle and keep one hand on the flame and the other on the side, the hand which is above the flame feels hotter.
The air around the candle gets heated up and rises, cool air from the sides come and take its place. 
Here, heat is getting transferred by convection.

Answer: Option A. ->
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(a) Reason: 2 Marks
(b) Definition: 1 Mark
(a) During daytime, the land gets heated faster than the water. The air over the land becomes hot and rises up. The cooler air from the sea rushes in towards
the land to take its place. The warm air from the land moves towards the sea to complete the cycle. The air from the sea is called the sea breeze. To receive the cooler sea breeze, the windows of the houses in coastal areas are made to face the sea.
(b) The wind that flows from land to sea after sunset is called the land breeze.

Answer: Option A. ->
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Thermometer definition: 1 Mark
Working: 2 Marks
A thermometer is an instrument which is used to measure the hotness of a substance.
The bulb comes in contact with an object and receives heat. This heat is conducted to the liquid inside the thermometer. This liquid which is usually Mercury expands uniformly depending on the amount of heat absorbed by the bulb. Depending on how much the liquid has expanded, the thermometer gives the respective reading.

Answer: Option A. ->
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(a) Uses: 2 Marks
(b) Reason: 1 Mark
(a) Insulators are very important when we are handling substances that are hot such as cooking utensils or welders, etc. Insulators are poor conductors, they do not transmit heat from the hot part of the object to the person holding the insulated part, thus keeping them safe.
(b) No, the other end of the wooden spoon will not become cold because wood is a bad conductor of heat, i.e. wood behaves as an insulator.

Answer: Option A. ->
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(a) Explanation: 2 Marks
(b) Explanation: 1 Mark
(a) When sun-rays fall on objects, the objects get heated by different amounts. Some of them are hotter since they absorb more heat than the others. It has been found that dark coloured objects are better absorbers and transmitters of heat.
In places where the weather is hot, it is advised that the outer walls of houses be painted white because light colour reflects most of the heat that falls on it. Therefore, the temperature inside the house does not increase very much. 
(b) Light colours reflect most of the heat coming from the sun and dark colours absorb most of the heat coming from the sun, that is why wearing light coloured clothes is much more comfortable than wearing dark coloured clothes in summers.

Answer: Option A. ->
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Each reason: 1 Mark
1) It has a low freezing point and a high boiling point. Hence it can be used for a wide range of temperature.
2) It has a shiny appearance due to which it can be easily seen through the glass of the thermometer tube.
3) It does not stick to the glass tube.