If the focal length of the biconvex lens is 25 cms, then the power of the lens will be
The lens strength in diopters is defined as the inverse of the focal length in meters. Thus 1/25 multiplied by 100 gives us the power of 4 dioptres which is postive for convex lens and negative for concave lens.
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
A stable nucleus (light with A < 10) has