Physics for IGCSE & O level - Rays And Waves (Section 3)
1
What are the two types of lens?
Răspuns
(C)
Convex and Concave
2
What is the angle of refraction when light passes from a medium with a refractive index of 1.0 into a medium with a refractive index of 1.0 at an angle of incidence of 0 degrees?
Răspuns
(A)
0 degrees
3
What is the name for the bending of light as it passes from one medium to another?
Răspuns
(B)
Refraction
4
What causes 'short sight' or myopia?
Răspuns
(B)
The lens focuses the image in front of the retina.
5
What happens to the speed of light when it enters a denser medium?
Răspuns
(B)
It decreases.
6
What kind of image is formed by the camera?
Răspuns
(A)
Real and inverted
7
What type of wave is used for satellite communication?
Răspuns
(B)
Microwaves
8
What is the approximate frequency of yellow light's wavelength?
Răspuns
(B)
5 x 10^14 Hz
9
What is the definition of a refractive index?
Răspuns
(B)
The ratio of the speed of light in vacuum to the speed of light in the medium.
10
Which of the following is/are a use of optical fibers?
Răspuns
A
B
11
In what situation does total internal reflection occur?
Răspuns
(B)
Light travels from a more dense to a less dense medium at an angle greater than the critical angle.
12
Which type of lens is thinner at the center and thicker at the edges?
Răspuns
(B)
Concave
13
Which part of the eye detects light and forms an image?
Răspuns
(B)
Retina
14
What is total internal reflection?
Răspuns
(A)
When all the light is reflected at the boundary of a medium
15
What happens to the light when it enters a glass prism?
Răspuns
(B)
It changes direction.
16
Which of the following can cause fluorescence?
Răspuns
(B)
Ultraviolet light
17
What type of radiation is used in the Remote Controllers?
Răspuns
(A)
Infrared
18
In short sight, what is the eye's focal length relative to the retina?
Răspuns
(B)
Too short
19
What is the function of a regenerator in digital communication?
Răspuns
(B)
To amplify and 'clean up' the digital signal.
20
What is the relationship between wavelength and frequency?
Răspuns
(C)
They are inversely proportional.
21
What is a key benefit of digital transmission over analogue transmission?
Răspuns
(B)
Is less susceptible to noise.
22
What happens to the image if an object moves closer to a convex lens?
Răspuns
(B)
Image moves further from the lens and becomes larger
23
What is the function of the aperture in a camera?
Răspuns
(B)
To control the amount of light entering the camera
24
Which of these can cause the image on the retina to be distorted?
Răspuns
A
B
C
25
If the angle of incidence is 30 degrees, what is the angle of reflection?
Răspuns
(B)
30 degrees
26
What is the speed of light in a medium with a refractive index of 2.0?
Răspuns
(C)
150,000 km/s
27
What is a characteristic of the image formed by a plane mirror?
Răspuns
(C)
It is virtual.
28
What part of the human eye is responsible for focusing?
Răspuns
(B)
Lens
29
In a camera, what is the purpose of the lens diaphragm (aperture)?
Răspuns
(B)
To control the amount of light
30
What kind of lens is used to correct short-sightedness?
Răspuns
(B)
Concave
31
Which type of wave is used to cook food in a microwave oven?
Răspuns
(B)
Microwaves
32
What is the relationship between the speed of light and the refractive index of a medium?
Răspuns
(B)
Inversely proportional
33
What is the relationship between the angles of incidence and reflection?
Răspuns
(A)
They are always equal.
34
What type of electromagnetic radiation is used in a microwave oven?
Răspuns
(B)
Microwaves
35
What are the main dangers associated with X-rays?
Răspuns
(D)
All of the above.
36
What happens to light rays as they pass through a convex lens?
Răspuns
(B)
They converge.
37
Which optical component utilizes total internal reflection?
Răspuns
(D)
Optical Fiber
38
What term describes light bending as it passes from one medium to another?
Răspuns
(B)
Refraction
39
What is the purpose of the transmission path in a telephone system?
Răspuns
(B)
To carry the electrical signals over a distance.
40
What is the main purpose of a camera lens?
Răspuns
(B)
To focus light onto the film or image sensor.
41
What is a main advantage of digital transmission?
Răspuns
(A)
It reduces noise
42
Which type of radiation is commonly used in medical imaging?
Răspuns
(C)
X-rays
43
What is the term for the bending of light?
Răspuns
(B)
Refraction
44
Which of these correctly describes how the speed of light changes as the wavelength increases?
Răspuns
(C)
It remains the same
45
What happens during dispersion?
Răspuns
(C)
Light is split into its component colors.
46
What happens to light as it passes from air into water (assuming a non-zero angle of incidence)?
Răspuns
(B)
It slows down and bends towards the normal.
47
What happens to the speed of light when it enters a denser medium, like glass?
Răspuns
(B)
It slows down.
48
Which of the following best describes the characteristics of a virtual image?
Răspuns
(C)
It appears to be located behind the mirror.
49
What is the term for light that spreads until it leaves its source?
