Physics questions
20027 published questions with worked solutions.
- A cup of tea cools from 65.50°C to 62.50°C in one minute in a room of temperature 22.5°C. How long will the same cup of tea take...
- A cup of tea cools from 80°C to 60°C in one minute. The ambient temperature is 30°C. In cooling from 60°C to 50°C, it will take
- A pan filled with hot food cools from 50°C to 49.9°C in 5 s. If it cools from 40°C to 39.9°C in 10 s, then room temperature is
- A body cools at the rate of 0.75 °C/s, when it is 50°C above the surrounding. Its rate of cooling, when it is 30 °C above the...
- A body in laboratory takes 4 minutes to cool from 61°C to 59°C. If the laboratory temperature is 30°C, then the time taken by it...
- The temperature of a body falls from 50°C to 40°C in 10 minutes. If the temperature of the surroundings is 20°C, then temperature...
- A hot liquid is kept in a big room. The logarithm of the numerical value of the temperature difference between the liquid and the...
- A gas at absolute temperature of 300 K has pressure of 4 10^ -10 N/m^2 . Boltzmann's constant k_B=1.38 10^ -23 J/K. The number of...
- Two beakers A and B low filled to the brim with water at 4°C. When A is heated and B is cooled, the water
- A body cools at the rate of 0.6 °C/s, when it is 40 °C above the surrounding. The rate of cooling, when it is at 20°C above the...
- The energy spectrum of a black body exhibits a maximum around a wavelength _0. The temperature of the black body is now changed...
- Two objects have exactly the same shape. Object A has emissivity of 0.3 and object B has emissivity of 0.6. If each radiates the...
- A metal sphere cools from 64°C to 50°C in 10 minutes and to 42°C in the next ten minutes. The ratio of rate of fall of...
- By what percentage should the pressure of a given mass of a gas be increased so as to decrease its volume by 20% at a constant...
- Two containers are filled; each with a different gas. The two containers are at the same temperature. If the molecular weights of...
- A carnot engine whose efficiency is 40%, takes in heat from a source maintained at a temperature of 500 K. It is desired to have...
- The equation for an ideal gas is PV = RT, where V represents the volume of [CPMT 1973, MP PMT 1983, RPMT 1985, RPMT 1994]
- The equation of state for 5 g of oxygen at a pressure P and temperature T, when occupying a volume V, will be [R is the gas...
- Two balloons are filled; one with pure He gas and the other with air respectively. If the pressure and temperature of these...
- A cylinder consists of hydrogen. Another cylinder of same volume has helium of same mass. If pressure of hydrogen is 4 atm, then...