EASY
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What is Regelation?

Important Questions on Thermal Properties of Matter

HARD
A 10 H inductor carries a current of 20 A. If the energy stored in this inductor melts ice at 0 °C, then the mass of the ice melted is [Latent heat of ice =2.26×103 J kg-1
EASY
In an experiment, a sphere of aluminium of mass 0.20 kg is heated up to 150°C . Immediately, it is put into water of volume 150 cc at 27oC kept in a calorimeter of water equivalent to 0.025 kg . The final temperature of the system is 40oC . The specific heat of the aluminium is(take 4.2 Joule=1 calorie )
MEDIUM
50 g of ice at 0 °C is mixed with 50 g of water at 80 °C. If the latent heat of ice is 80 cal g-1 and specific heat of water is 1 cal g-1 °C-1, then the final temperature of mixture is
MEDIUM
A solid metal weighing 150 g melts at its melting point of 800 °C by providing heat at the rate of 100 W. The time taken for it to completely melt at the same temperature is 4 min. What is the specific latent heat of fusion of the metal?
EASY
A closed bottle containing water at 30oC is open on the surface of the moon. Then-
HARD

Explain the following temperature versus time graph:

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EASY
Latent heat of vaporisation of water is 22.6×105 J kg-1. The amount of heat needed to convert 100 kg of water into vapour at 100 °C is
HARD

A thermally insulated cubical box of side length 20 cm and wall thickness 2 cm containing 2 kg of ice is closed on all sides. The mass of ice melted in 10 hours is (Thermal conductivity of the material of the box =0.01 Wm-1 K-1, latent heat of ice =360×103 J kg-1 and ambient temperature =40 °C)

MEDIUM
A thermally insulated vessel contains 150 g of water at 0°C . Then the air from the vessel is pumped out adiabatically. A fraction of water turns into ice and the rest evaporates at 0°C itself. The mass of evaporated water will be closest to: (Latent heat of vaporization of water =2.10×106 J kg-1 and Latent heat of Fusion of water =3.36×105 J kg-1 )
MEDIUM
1 kg of water, at 20 °C is heated in an electric kettle whose heating element has a mean (temperature averaged) resistance of 20Ω. The rms voltage in the mains is 200 V. Ignoring heat loss from the kettle, time taken for water to evaporate fully is close to
[ Specific heat of water =4200 J kg-1 °C-1 Latent heat of water =2260 kJ kg-1 ]
EASY
The physical quantity that determines whether or not a given system A is in thermal equilibrium with another system B is called
EASY
If pressure increased on a piece of wax, the melting point of wax
EASY

A steam engine intakes 50 g of steam at 100°C per minute and cools it down to 20°C. If latent heat of vaporization of steam is 540 cal g-1, then the heat rejected by the steam engine per minute is _____ ×103 cal

(Given : specific heat capacity of water : 1 cal g-1C-1)

EASY

Heat required to melt 1 g of ice is 80 cal. A man melts 60 g of ice by chewing in one minute. His power is______

MEDIUM
Steam at 100 oC is passed into 20 g of water at 10 oC. When water acquires a temperature of 80oC, the mass of water present will be:
[Take specific heat of water =1 cal g-1 oC-1 and latent heat of steam =540 cal g-1]
EASY
A piece of ice falls from a height h so that it melts completely. Only one-quarter of the heat produced is absorbed by the ice and all energy of ice gets converted into heat during its fall. The value of h is:
(Latent heat of ice is 3.4×105J kg-1 and g=10N kg-1)
EASY
Two systems are in thermal equilibrium. The quantity which is common for them is
EASY
What is the unit of latent heat? (Choose from newton, joule, celsius)
HARD
Steam at 100°C is passed into 1.1 kg of water. It is contained in a calorimeter, which is equivalent to 0.02 kg at 15°C, till the temperature of the calorimeter and its contents rises to 80°C. The mass of the steam condensed in kg is 
EASY

Two substances A and B of equal mass m are heated at a uniform rate of  6 cal s1 under similar conditions. A graph between temperature and time is shown in the figure. The ratio of heat absorbed HAHB by them during fusion is

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