Light - Post Assessment

A ray of light in a transparent medium of refractive index 1.8 is incident on the surface as shown. The light enters air.

What is the angle between the refracted ray and the normal in air?

• 29°

• 33°

• 54°

• 64°

A shoe shop puts a mirror on the wall so that customers can look at their shoes. The length of the mirror is 50cm. A customer has eyes 150cm above ground level.

The bottom of the mirror is at height h above the ground. What is the smallest value of h that allows the customer to see an image of his shoes in the mirror?

• 0 cm

• 25 cm

• 50 cm

• 75 cm

An object is placed in front of a plane mirror. The image produced is

• real and smaller than the object.

• real and the same size as the object.

• virtual and smaller than the object.

• virtual and the same size as the object.

A ray of light enters a glass block at an angle of incidence i producing an angle of refraction r in the glass.
Several different values of i and r are measured, and a graph is drawn of sin i against sin r.
Which graph is correct? 

• A
• B
• C
• D

When white light is dispersed by a prism, compared with blue light, the red light is

• slowed down less and refracted less.
• slowed down less and refracted more.
• slowed down more and refracted less.
• slowed down more and refracted more. 

A semi-circular block is made from a plastic. A ray of light passes through it at the angles shown. 
To two decimal places, what is the refractive index of the plastic?

• 1.25
• 1.41
• 1.51
• 1.61 

Absolute refractive index of any medium is always _______.

• less than 1
• greater than 1
• 1
• 0

Light has the lowest velocity in which medium?
flint glass n=1.70
barium glass n=1.60
crown glass n=1.523
water n=1.33
diamond n=2.45

• diamond
• water
• flint glass
• barium glass

Tags

NGSS.MS-PS4-2

When light passes at an angle to the normal from one material into another material in which its speed is lower

• it is bent towards the normal.
• it always lies along the normal.
• it is unaffected.
• it is bent away from the normal.

What type of image is formed when rays of light actually intersect?

• real
• virtual
• curved
• projected