A copper rod, 5m long, when heated through 10ºC, expands by 1mm. If a second copper rod, 2.5m long, is heated through 5ºC, by how much will it expand?
A safety precaution designed to prolong the life of a lead acid accumulator is
The mass of water vapour in a given volume of air is 0.05g at 20°C, while the mass of water vapour required to saturate it at the same temperature is 0.15g. Calculate the relative humidity of the air.
The angular dispersion of a prism depends on
Which of the following statements are correct of the production and propagation of waves?
I. vibration produces waves
II. waves transmit energy along the medium
III. the medium through which the wave travels does not travel with the wave
IV. waves do not require any medium for transmission