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Correct Answer is: (c) Q₁ - W₁ = Q₂ - W₂ 

Correct Answer is: (d) 42 K

ΔT_A = ΔQ/C_p  ΔT_B = ΔQ/C_V

∴ ΔT_B/ΔT_A = C_p/C_V = 7/5 for diatomic gas

ΔT_B = 7/5 x 30 K = 42 K.

There are three modes of heat transfer:

1. conduction 

2. convection 

3. radiation.

In places of hot climate it is advised that the outer wall of houses be painted white because white colour reflects heat and the houses do not heat up too much.

Rajasthan being a desert, temperature is very high. So there is excess heat. White colour doesn’t absorb the heat but reflects back, so houses will not become hot due to excess heat and inside of the house will be cool. So the houses in Rajasthan are painted white.

(a) The hotness of an object is determined by its Temperature. 

(b) Temperature of boiling water cannot be measured by a Clinical thermometer thermometer. 

(c) Temperature is measured in degree Celsius

Heat transfer, in the form of waves from one place to another. It does not require any medium.

(a) Thermometer (i) or (iii) for measuring body temperature and (ii) for measuring the temperature of boiling water.

(c) Both have normal body temperature. 

The correct option is D) all.

1. On a frosty early morning, the temperature of air outside a warm room is lower than the dew point.

2. Hence, when you enter the room from outside, some water vapour in the room condenses on the glass of your spectacles, i.e., the spectacles ‘steam up’.

1. During a cold night, the temperature of air may fall to the dew point, or even below the dew point.

2. If the temperature falls below the dew point, the excess of water vapour in air condenses on the surfaces of cold bodies and dew is formed.

Correct option is  C) falls

Correct option is  A) 200 K

Maximum and minimum temperature of a day, air pressure, rainfall, wind speed and humidity are called measuring components of weather.

1) Maximum and minimum temperature of a day: 

Maximum and minimum tempera-ture of a day are the highest and lowest temperature recorded respectively during a day. Six’s maximum and minimum thermometer is one of the meteorological in-struments used to measure maximum (highest) and minimum (lowest) temperatures of a place in a day.

2) Air pressure: 

The force applied by air on any surface in contact is called “air pres-sure”. Air pressure is measured in height of mercury level in centimeters and it is measured with a barometer. 

3) Rainfall: 

The amount of water falling in rajn within a given time and area is called Rain fall. Rainfall is measured in millimeters by using a rain gauge. 

4) Wind speed: 

Wind move is caused by difference in the air pressure in two places. The speed of wind can be measured using a device called an anemometer. 

5) Humidity: 

The water vapour present in the air is called humidity Hygrometer is used to measure humidity in air and it is expressed in grams per cubic meter.

The correct option is A) g/cubic meter.

The correct option is D) none.

Correct option is: A) 45° C

Correct option is: B) 57° C

The mercury level falls down that shows temperature of the mercury level decreases.

Correct option is  A) A to B

Correct option is  A) 27 K

On Kelvin scale of temperature zero mark is when no molecular motion occurs. Ice point is at 273 and steam point is at 373 K. Thus 0 K = – 273°C and one degree on Kelvin scale is same as one degree on Celsius scale.

1. Heat is a thermal energy that flows from hot body to cold body. Temperature is measure of the hotness or coldness of a body.

2. Temperature decides direction of heat (energy) flow, whereas heat is energy itself that flows.

The mercury level rises up that means temperature of the mercury level increases.

When we bring two objects of different temperature together, energy will always be transferred from hotter to the cooler object. 

Here, also heat will flow from hot milk tumbler to tub of cold water.

D) average kinetic energy

C) Kelvin scale

The moving air creates low pressure. Hence the postcard lifts up due to the higher pressure on the card from air inside the glass.

 B)  \(\cfrac{m_1T_1+m_2T_2}{m_1+m_2}\)

(a) begin to move faster

(d) The average kinetic energy of the. molecules of an object.

(a) The molecules of A move faster on an average than the molecules of B

The degree of hot or cold of a body is called heat/temperature.

Solid expands on heating and contracts on cooling.

Gases expands on heating and occupies more space. They contracts on cooling and occupy less space.

Temperature is expressed in degree degree centigrade/ Joule.

In change the state Q = mL 

m = 5 gm, L = Latent heat of fusion = 80 Cal/gm 

Q = mL = 5 × 80 = 400 cal.

Substances changes from liquid to gas at constant temperature, it is called condensation/boiling point.