IGCSE Physics | Practice Test | 25 Questions
Define the term normal as used in reflection diagrams.
Define the angle of incidence.
Define the angle of reflection.
State the law of reflection.
State the three characteristics of the image formed by a plane mirror.
What is meant by a virtual image?
From which line are the angle of incidence and the angle of reflection always measured?
A ray of light hits a plane mirror at an angle of incidence of 55°. State the angle of reflection.
Is the image in a plane mirror larger than, smaller than, or the same size as the object?
An object is placed 8 cm in front of a plane mirror. State how far behind the mirror the image appears.
A ray of light hits a plane mirror at an angle of incidence of 35°.
(a) State the angle of reflection.
(b) Calculate the angle between the incident ray and the reflected ray.
A ray of light hits a plane mirror. The angle between the ray and the mirror surface is 25°.
(a) Find the angle of incidence.
(b) State the angle of reflection.
The angle between an incident ray and its reflected ray is 64°. Find the angle of incidence.
An object is placed 15 cm in front of a plane mirror.
(a) State how far behind the mirror the image appears.
(b) Calculate the total distance from the object to its image.
Explain why the image formed by a plane mirror cannot be projected onto a screen.
A student writes: “The angle of reflection is the angle between the reflected ray and the mirror surface.”
Correct this statement and explain what the angle of reflection is actually measured from.
A ray of light hits a plane mirror and reflects back along exactly the same path as the incident ray. State the angle of incidence and explain why this happens.
An object is moved from 6 cm to 18 cm in front of a plane mirror. Describe what happens to:
(a) The distance of the image from the mirror.
(b) The size of the image.
An object is 20 cm in front of a plane mirror. The object then moves 5 cm closer to the mirror.
(a) State where the image now appears.
(b) How far has the image moved compared to its original position?
The angle between an incident ray and the mirror surface is 50°. Show that the angle between the incident ray and the reflected ray is 80°. Show all your working.
Describe the image formed by a plane mirror. For each of the three characteristics, give a brief explanation of what it means. Then explain why the image is described as “virtual” rather than “real”.
An object is placed 7 cm in front of a plane mirror. Supplement
(a) Describe step by step how to draw and correctly reflect two rays from the object.
(b) Explain how the reflected rays are used to find the position of the image.
(c) State the expected distance of the image behind the mirror.
A student makes three statements about the image in a plane mirror. For each statement, say whether it is correct or incorrect and give a full explanation.
(a) “The image is behind the mirror at the same distance as the object is in front.”
(b) “The image is the same size as the object.”
(c) “I can project the image onto a screen if I use a bright enough light source.”
A ray of light hits a plane mirror. The angle between the incident ray and the mirror surface is 30°.
(a) Find the angle of incidence.
(b) Find the angle of reflection.
(c) Find the angle between the incident ray and the reflected ray.
(d) A second ray hits the same mirror. Its reflected ray makes an angle of 20° with the normal. Find the angle this incident ray makes with the mirror surface.
A student investigates reflection using a plane mirror and a ruler. Supplement
(a) A pin (object) is placed 9 cm in front of the mirror. State where the image appears and give the total distance from the pin to its image.
(b) The student draws a ray from the pin that hits the mirror at 40° to the mirror surface. Find the angle of reflection.
(c) Describe step by step how to use two reflected rays to locate the position of the image.
(d) The student moves the pin to 14 cm from the mirror. State the new image position and the new total distance from the pin to its image.
