3. A bus travelling the first one third distance at a speed of 10 km/h, the next one third at 20 km/h and the last one-third at 60 km/h. The average speed of the bus is ?

2. A car moves a distance of 200 m. It covers the first half of the distance at speed 40 km/h and the second half of distance at speed v. The average speed is 48 km/h. Find the value of v.

89. The following truth table corresponds to the logic gate ?

4. The depletion layer in the p−n junction region is caused by ?

3. Ratio of intensities of two waves are given by 4 : 1. Then the ratio of the amplitudes of the two waves is ?

9. A beam of monochromatic light is refracted from vacuum into a medium of refractive index 1.5, the wavelength of refracted light will be ?

8. Green light of wavelength 5460 Å is incident on an air-glass interface. If the refractive index of glass is 1.5 , the wavelength of light in glass would be (c = 3 × $10^8$ $ms^−1$) ?

When air is replaced by a dielectric medium of force constant K, the maximum force of attraction between two charges, separated by a distance ___ ?

Physical independence of force is a consequence of