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Rate of Loss of Heat=    Rate of Cooling=        According to Newton's Law of Cooling  I.e              When body Cools by Radiation from    to theta  in time t                                                                                                                                       Then                                                                                                  ...
If an ordinary body at temperature  is surrounded by a body at a temperature                       Then according to Stefan Boltzmann law                                 
Wien's displacement law is useful for determining the temperatures of hot radiant objects such as stars, and it is also useful for a determination of the temperature of any radiant object whose temperature is far above that of its surroundings.
   According to  Kirchhoff's law, the ratio of emissive power to absorptive power is the same for all surfaces at the same temperature and is equal to the emissive power of a perfectly black body at that temperature.  I.e   And as for perfectly black body A = 1
No. Let's understand this in this concept.
Here are some examples of different types of radiation: ultraviolet light from the sun visible light from a candle  
Give one everyday life examples of Convection ?
Lattice vibration in metal is mainly responsible for heat conduction through metals
No, heat flow from high temperature to low temperature naturally but we can transfer heat from low temperature to high temperature by using some equipment like refrigerator or heat pump.
Because in this the heat energy which is supplied to change the state is latent heat. Latent heat is hidden heat which does not raise the temperature but it has to be applied to change the state of the substance
There is only a very negligible (if any) transfer of energy to the walls of the container or outside. It means the wall of equipment is perfectly insulated.
  For water - Triple point exist at - Pressure = 0.0062 bar or, 62 Pascal                                                     Temperature = 0.01  or, 273.16 K     
Latent heat of vaporisation is more than the latent heat of fusion.
Mechanical energy can be converted into heat. This important physical observation is known as the mechanical equivalent of heat. So, mechanical equivalent of heat states that motion(Work) and heat are mutually interchangeable and that in every case, a given amount of work would generate the same amount of heat, provided the work done is totally converted to heat energy.
It is because, only the top layer of the lake or river freezes. And as we know that the density of ice is lower than the water, so it comes at the top surface. As the thermal conductivity of ice is very less so the heat is not conducted by the lower water (in which fish is living). So it makes fish to survive even in icy water because heat does not flow from water to the atmosphere and the...
Strain is measurable quantity means it can be measured with the help of some mechanical equipment like Extensometer. But stress is not measured, it is calculated with the help of strain.
 Time period of a simple pendulum =   Due to rise in temperature the length of the simple pendulum increases and which give rise to the simple pendulum.
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