The thermal conductivity of copper is 4 items that of brass. Two rods of copper and brass having same length and cross-section are joined end to end. The free end of copper is at 0^o C and the free end of brass is at 100^o C. The temperature of the junction is

If the focal length of the biconvex lens is 25 cms, then the power of the lens will be

A body attached to a spring balance weighs 10 kg on the Earth. The body attached to the same spring balance is taken to a planet where gravity is half that of the Earth. The balance will read

Body A of mass 2 kg and another body B of mass 4 kg and of same material are kept in the same sunshine for some interval of time. If the rise in temperature is equal for both the bodies, then which one among the following in this regard is correct?

When a solid object is immersed in water, there is a loss in its weight. This loss is

An electric lamp of 100 watt is used for 10 hours per day. The ‘units’of energy consumed in one day by the lamp is