Question : In a filament-type light bulb, most of the electric power consumed appears as

Option 1: visible light

Option 2: infrared rays

Option 3: ultraviolet rays

Option 4: fluorescent light

Question : Dioptre is the unit of:

Option 1: power of a lens

Option 2: focal length of a lens

Option 3: light intensity

Option 4: sound intensity

Question : Sir C.V. Raman was awarded the Nobel Prize for his work on:

Option 1: Light scattering

Option 2: Radioactivity

Option 3: Cryogenics

Option 4: Sonometer

Question : A light wave is incident over a plane surface with velocity x. After reflection, the velocity becomes:

Option 1: x/2

Option 2: x

Option 3: 2x

Option 4: x/4

Question : Which of these waves can be polarised?

Option 1: Sound waves in the air

Option 2: Longitudinal waves on a string

Option 3: Transverse waves on a string

Option 4: Light waves