Question
What causes the change in direction when light travels from air into glass?
The amplitude of the light changes.
The colour of the light changes.
The frequency of the light changes.
The speed of the light changes.
Answer/Explanation
Ans: D
Question
The diagram shows light incident at a glass-air boundary. The angle of incidence i of the ray is
greater than the critical angle.
Which line shows the path of the light after it meets the boundary?
Answer/Explanation
Ans: B
Question
The diagram shows a beam of light travelling through glass and meeting a glass-air interface.
Which row correctly describes what is happening at the glass-air interface?
| angle of incidence at the interface | observation |
A B C D | 30° 30° 60° 60° | some internal reflection total internal reflection some internal reflection total internal reflection |
Answer/Explanation
Ans: A
Question
In which situation is the wavelength of the wave changed?
light from the Sun passing from air into water
radio waves travelling from an Earth satellite to the Moon
sound reflecting from a wall
water waves passing through a narrow gap
Answer/Explanation
Ans: A
In refraction phenomenon, when a wave travels form one medium to another medium then the speed and wavelength of the wave changes but the frequency remains the same.
Question
A ray of light is incident on the surface of a glass block.
Which row describes how the speed and the direction of the ray of light change when it enters the glass?
| speed in glass | direction in glass |
A | decreases | closer to the normal |
B | decreases | further from the normal |
C | increases | closer to the normal |
D | increases | further from the normal |
Answer/Explanation
Ans: A