Sun appears red in colour at sunrise and sunset due to

• the fact that sun emits only red colour at that time

• red light having longer wave length scatters away

• that sun comes out of the mountains

• that sun comes out of the mountains

Which one of the following processes is responsible for the glittering of air bubble rising through water?

• Reflection of light

• Refraction of light

• Total internal reflection of light

• Total internal reflection of light

63.

In an optical fibre, the signal is transmitted

• in a straight line path

• in a curved path

• due to total internal reflection

• due to total internal reflection

Which one of the following is not a non-conventional source of energy?

• Solar Energy

• Natural Gas

• Wind Energy

• Wind Energy

Which one among the following components is used as an amplifying device?

• Transformer

• Diode

• Capacitor

• Capacitor

The unit of measurement of noise is

• Decibel

• Hertz

• Amplifier

• Amplifier

Which one of the following is an ohmic conductor?

• Germanium

• Silicon

• Carbon

• Carbon

Anemometer is an instrument meant for measuring .............

• velocity

• air masses

• wind speed

• wind speed

The spring balance works on the principle of ............

• Boyle's Law

• Hooke's Law

• Bernoulli's principle

• Bernoulli's principle

If there were no gravity,  which of the following will not be there for a fluid?

• Viscosity

• Surface Tension

• Pressure

• Pressure