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The temperature of water when boiling is 100°C.

(b) The air particles to your body

If the normal body temperature, (37°C or 98.6°F) is lower than what it is, then it is called hypothermia.

In such a case, the body feels cold sensation. When we are too cold, our blood vessels narrow. This reduces blood flow to our skin to save body heat. We may start to shiver. When the muscles tremble this way, it helps to make more heat.

Hypothermia can be serious one or even deadly. Low body temperature usually happens from being out in cold weather. But it may also be caused by alcohol or drug use, going into shock, or certain disorders such as diabetes or low thyroid.

A low body temperature may occur with an infection. This is most common in newborns, older adults, or people who are frail. A very bad infection may also cause an abnormal low body temperature.

[✓] One litre water

(b) The coffee to your body

1. kelvin

2. 100°C

3. Temperature

[✓] Can in five litre boiled water.

1. During winter season, in the night times, atmospheric temperature goes down.

2. The surfaces of window panes, flowers, grass, etc. become colder. 

3. The water vapour molecules touch the surfaces, gets cooled and lost its energy. 

4. Then water vapour condenses on the surface and water drops formed. 

5. The water droplets condensed on such surfaces are known as dew.

1) Yes, the reverse process of evaporation takes place.

2) When the vapour molecules lose their kinetic energy which leads to lower the temperature, they convert into droplets. 

3) This process is called condensation.

The process of escaping molecules from the surface of a liquid at any temperature is called evaporation.

Evaporation is a surface phenomenon and is a cooling process.

The rate of evaporation of a liquid depends on its surface area temperature and the amount of vapor already present in the surrounding air.

1. No, they are different. 

2. Evaporation takes place at any temperature. 

3. But boiling occurs at particular temperature called the boiling point.

C) a, b, c and d

Correct Answer is: (b) k₁θ₁ + k₂θ₂/k₂ + k₂

The given situation is like two resistances in series. We define the heat current I = θ₁ - θ₂/R

As the resistances are in series, they carry the same current. Let θ be the temperature of their junction.

I = θ₁ - θ/R₁ = θ - θ₂/R₂, where R₁ = l/k₁A and R₂ = l/k₂A

or  θ₁ - θ/θ - θ₂ = R₁/R₂ = k₂/k₁.

Thermos flask was invented by Sir James Dewar.

Correct option is  B) Calorie

Correct option is  A) Joule

Yes, shape and size changes in the expansion on heating a metal.

This is because heat is transferred from one end to another end by the mode of conduction.

When you heat a piece of metal it expands on heating.

Puri swells when it is put in hot oil, because water in the substance is expanded in the hot oil.

The level of mercury in thermometer increases when it is kept in the mouth of a person suffering from fever. This is due to expansion of mercury on heating.

The metal expands on heating and contracts on cooling.

Smoke and hot air moves up because it expands and becomes lighter.

1. This is due to increase in the energy of particles present in these substances. 

2. Particles of substances occupy more space when they get heated. 

3. This is the reason for in the expansion of rails, mercury in thermometer, air inside the puri etc

The correct option is C) Plastic.

1. The heat when heat energy flows from hotter body to our body. We feel hot. Here we gain heat energy from the hotter body. 

2. We feel cool, when heat energy flows from our body to colder body. Here, we lose heat energy.

Smoke and hot air moves up because it expands and becomes lighter. . .

The correct option is C) It easily sticks to the sides of glass tube..

The correct option is A) hot air balloons.

(i) Specific heat.

(ii) Specific heat: The amount of heat energy required to raise the temperature of a unit mass of an object by 1 °C.

(iii) According to the rule/principle of heat exchange, heat energy lost by the hot object = heat energy gained by the cold object.

In this activity, heat absorbed by the iron sphere is transmitted more in the wax, hence the sphere goes deepest into the wax, while the lead sphere absorbs less heat, resulting in less transmission of heat in the wax, hence, the sphere goes the least depth into the wax.

The amount of heat energy required to raise the temperature of a unit mass of an object by 1°C is called the specific heat capacity of that object.

Correct Answer is: (c) sink if γ > 3α

Correct Answer is: (b) 3/2 

p^{1 - γ} T ^γ = constant

or p ∝ T [^γ /(γ - 1)]

Here, p ∝ T³

or γ / γ - 1 = 3 or γ = 3/2. 

Heat is a form of energy which flows. It is the energy of motion of molecules constituting the body. 

The unit of heat is same as that of energy, The S.I. unit of heat is joule (abbreviated as J) and other common units of heat are calorie and kilo calorie, where 1 kcal = 1000 cal.