Why is the freezing chest in a refrigerator fitted near its top ?

Why dry ice acts as a refrigerant?

A Carnot heat engine has an efficiency of 10% . If the same engine is worked backward to obtain a refrigerator, then find its coefficient of performance.

Consider the energy density in a solenoid at its centre and that near its ends. Which of the two is greater?

Explain why the molecular weight of KCl determined by the depression in the freezing point method does not agree with its correct theoretical molecular weight. What do you expect is its molecular weight as determined by the experiment ?

Statement- 1 : Coolant coils are fitted at the top of a refrigerator , for formation of convection current. Statement- 2 : Air becomes denser on cooling.

Why the inductance per unit length for a solenoid near its centre is different from inductance per unit length near its ends?

Why is the fuse wire fitted in a porcelain casing?

Explain why some times foaming is seen in river water near the place where sewage water is poured after treatment ?

In Regnault's apparatus for measuring specific beat capcity of a solied, there is an intel and an inlet and an outlet in the sterm cahmober .The intel is near the top and the outlet is near the bottom .Why is it better than the opposite choice where the inlet is near bottom and the outlet is near the top ?

Why are raw foods kept below in refrigerators while cooked foods are kept above