?A ray of white light strikes the?surface of an object. If all the colours are reflected the surface would appear:
1). ?Black
2). White?
3). Grey
4). Opaque
1. Optical fibres are based on the phenomenon of
2. 1 m/s equals ________ km/hr
4. The ordinary and maximum tolerance limit of sound by human being is
5. A wheel-barrow is an example of
6. ?In an isothermal expansion of a gas?
8. Short sight in human eye can be corrected by using proper
9. The centre of gravity of a sprinter during the race lies
10. In hydro power station, the motion produced in turbines is due to