A transparent rectangular block 5.0cm thick is placed on a black dot. The dot when viewed from above is seem 3.0cm from the top of the block calculate the refractive index of the material of the block.
The velocities of light in air and glass are 3.0 x10\(^8\)ms\(^{-1}\) and 1.8 \(\times \)10\(^8\) ms\(^{-1}\) respectively. Calculate the sine of the angle of incidence that will produce an angle of refraction of 30° for a ray of light incident on glass.
An object is placed 36cm from a converging lens of focal length 24cm.If a real image which is 4cm high is formed, Calculate the height of the object.
The change of the direction of a wave-front because of a change in the velocity of the wave in another medium is called?
