## Question

### Solution

Correct option is

3 m

If x be the diameter of the disc, then

#### SIMILAR QUESTIONS

Q1

The wavelength of light diminishes μ times in the medium. A diver from inside water (μ = 1.33) looks at an object whose natural colour is green. He sees the object as:

Q2

Air has refraction index of 1.0003. The thickness of air column, which will have one more wavelength of yellow light (6000 Å) than in the same thickness of vacuum is:

Q3

A ray of light travelling inside a rectangular glass block of refractive index  is incident on the glass-air interface at an angle of incidence of 45o. The refractive index of air is one. Under these conditions the ray:

Q4

The critical angle of for light going from medium x into medium y is θ. The speed of light in medium x is v. The speed of light in medium y is:

Q5

Monochromatic light of wavelength  travelling in a medium of refractive index n1 enters a denser medium of refractive index n2. The wavelength in the second medium is:

Q6

When seen in green, the saffron and green portions of our national flag will appear to be:

Q7

Light travels through a glass plate of thickness t and having refractive indexμ. If c be the velocity of light in vacuum, the time taken by the light to travel this thickness of glass is:

Q8

are the electric permittivity and the magnetic permeability in a free space, ε and μ are the corresponding quantities in the medium, the index of refraction of the medium is:

Q9

A perfectly reflecting mirror has an area of 1 cm2. Light energy is allowed to fall on it for one hour at the rate of 10 W/cm2. The force that acts on the mirror is:

Q10

A transparent cube of 15 cm edge contains a small air bubble. Its apparent depth when viewed through one face is 6 cm and when viewed through the opposite face is 4 cm. Then the refractive index of the material of the cube is: