Light
Each subtopic includes About section, revision page link, 10 preview questions, and practice CTAs.
How light travels in straight lines
SubtopicHow light travels in straight lines under Light for Grade 5 IGCSE.
Preview questions (no answers)
- 1.
When drawing light rays entering a human eye from a lamp, the arrows should point:
A.Away from the eye toward the lamp
B.From the lamp toward the eye
C.In both directions
D.Upward toward the ceiling
- 2.
If you are in a completely dark room with no light sources, can you see a red apple?
A.Yes, because the apple is red
B.Yes, if you wait for your eyes to adjust
C.No, because there is no light to reflect off the apple into your eyes
D.No, because apples only exist in the light
- 3.
A light ray can be blocked by:
A.A transparent object
B.An opaque object
C.A shadow
D.Clear air
- 4.
What happens to light when it hits a piece of cardboard?
A.It goes through it
B.It is blocked because cardboard is opaque
C.It turns into a rainbow
D.It makes the cardboard transparent
- 5.
A periscope allows a person to see 'around' an obstacle. Does this mean the light has bent?
A.Yes, the periscope's tubes curve the light.
B.No, the light still travels in straight lines but is reflected by mirrors.
C.Yes, mirrors are designed to bend light rays into curves.
D.No, light only travels through the mirrors and skips the space between.
- 6.
What is the name of the dark area where light is completely blocked by an object?
A.The reflection
B.The shadow
C.The beam
D.The rainbow
- 7.
If you are in a completely dark room with no light sources, what will you see?
A.Your own shadow.
B.The outlines of the furniture.
C.Nothing at all.
D.Reflections of yourself.
- 8.
A light beam travels through a glass block and exits back into the air. If the beam enters the glass at an angle, it changes direction. What happens to the speed of the light during this process?
A.It stays the same, which is why it must travel in a straight line.
B.It slows down in the glass and speeds up in the air, but travels straight within each material.
C.It speeds up in the glass, causing it to curve.
D.It stops moving for a fraction of a second when hitting the glass.
- 9.
If you are in a completely pitch-black room with a mirror, why can't you see your reflection?
A.The mirror needs light to travel in a straight line from a source, reflect off you, and then reflect off the mirror to your eyes.
B.Mirrors only work in the presence of natural sunlight.
C.The darkness absorbs the straight lines of light before they can reach the mirror.
D.Your eyes cannot process straight lines of light in the dark.
- 10.
Why do shadows have fuzzy edges when created by the light from a frosted light bulb?
A.The frosted glass scatters light, creating many 'straight lines' from different points on the bulb.
B.Frosted glass causes light to travel in wavy lines instead of straight lines.
C.The bulb is colder, which affects how light travels.
D.The shadow is reflecting off the frost on the bulb.
Download the worksheet for Light - How light travels in straight lines to practice offline. It includes additional chapter-level practice questions.
Reflection and the law of reflection
SubtopicReflection and the law of reflection under Light for Grade 5 IGCSE.
Preview questions (no answers)
- 1.
Which of these must be present for you to see a reflection in a mirror in a room?
A.A camera
B.A light source
C.A window
D.A computer
- 2.
What happens when you shine a light at a dark, matte (not shiny) black wall?
A.It reflects a perfect image
B.Very little light is reflected, most is absorbed
C.The light passes through the wall
D.The wall starts to glow like a lamp
- 3.
If you look at a clock in a mirror and it looks like it is 9:00, what is the actual time?
A.9:00
B.12:00
C.3:00
D.6:00
- 4.
What is the primary difference between a mirror and a piece of glass in a window?
A.Glass is always thick, mirrors are thin
B.Glass lets light through, a mirror reflects most of it
C.Mirrors are made of wood
D.Glass cannot reflect any light
- 5.
If a light ray strikes a mirror at an angle of to the normal, what is the angle between the incident ray and the reflected ray?
A.B.C.D. - 6.
Which statement about images in a plane mirror is true?
A.The image is upside down
B.The image is larger than the object
C.The image is the same size as the object
D.The image is blurred
- 7.
What is the angle between the normal and the mirror surface?
A.B.C.D. - 8.
A ray of light strikes a mirror at an angle of incidence of . If the mirror is rotated by towards the incident ray, what is the new angle of reflection?
A.B.C.D. - 9.
Why is the image in a plane mirror called a 'virtual' image?
A.Because it is not actually there and light rays do not pass through it.
B.Because it is formed by a computer.
C.Because it is blurry.
D.Because it is upside down.
- 10.
A ray of light is directed at a mirror. The angle of reflection is . If the angle between the incident ray and the reflected ray is , what is the value of ?
A.B.C.D.
Download the worksheet for Light - Reflection and the law of reflection to practice offline. It includes additional chapter-level practice questions.
Refraction and the spectrum of light
SubtopicRefraction and the spectrum of light under Light for Grade 5 IGCSE.
Preview questions (no answers)
- 1.
Which of these is the primary source of light that creates a natural rainbow?
A.The Moon
B.The Sun
C.A flashlight
D.Streetlights
- 2.
Which color comes directly before Indigo in the spectrum?
A.Blue
B.Green
C.Yellow
D.Orange
- 3.
A prism works because different colors of light ______________ by different amounts.
A.Reflect
B.Refract
C.Disappear
D.Stop
- 4.
Which of these is a result of light refraction in the atmosphere?
A.A shadow on the ground
B.The twinkling of stars
C.An echo
D.Night time
- 5.
Which of these is the correct order of the last three colors of the spectrum, starting from the middle?
A.Blue, Indigo, Violet
B.Violet, Indigo, Blue
C.Green, Blue, Violet
D.Indigo, Blue, Violet
- 6.
If light travels from a more dense medium (glass) to a less dense medium (air), what happens to its speed?
A.It slows down
B.It speeds up
C.It stays the same
D.It stops
- 7.
Which type of lens would you find in a peephole of a door to give a wide-angle view?
A.Convex lens
B.Concave lens
C.Prism
D.Flat glass
- 8.
Why do we use prisms in some high-quality binoculars instead of just mirrors?
A.Prisms are lighter than mirrors.
B.Prisms can use Total Internal Reflection to reflect of the light without the loss that occurs with mirrors.
C.Prisms make the image smaller so it fits in the eye.
D.Prisms change the color of the image to make it clearer.
- 9.
A ray of light passes from glass into water. How does the bending of this ray differ from a ray passing from air into water?
A.It will bend toward the normal because water is denser than glass.
B.It will bend away from the normal because water is less dense than glass.
C.It will not bend at all because both are liquids or solids.
D.It will turn into a rainbow immediately.
- 10.
Which of these scientists is most famously associated with the study of the spectrum and the discovery that white light is made of many colors?
A.Albert Einstein
B.Isaac Newton
C.Thomas Edison
D.Charles Darwin
Download the worksheet for Light - Refraction and the spectrum of light to practice offline. It includes additional chapter-level practice questions.
How we see objects and the function of the eye
SubtopicHow we see objects and the function of the eye under Light for Grade 5 IGCSE.
Preview questions (no answers)
- 1.
Which of these is a source of light you might use at night during a power cut?
A.A book
B.A candle
C.A teddy bear
D.A mirror
- 2.
If you see a red apple, what is happening to the light?
A.The apple is making its own red light
B.Red light is reflecting from the apple to your eyes
C.Your eyes are sending red light to the apple
D.The apple is a mirror
- 3.
Which part of the eye changes shape to help focus on objects that are near or far?
A.The lens
B.The pupil
C.The iris
D.The retina
- 4.
What do we call the dark area where light has been blocked by an object?
A.A reflection
B.A beam
C.A shadow
D.A ray
- 5.
What is the relationship between light and shadows?
A.Shadows are made of a special kind of 'dark light'.
B.Shadows are areas where light has been blocked by an opaque object.
C.Shadows only exist when there are two or more light sources.
D.Shadows are reflections of the object on the floor.
- 6.
Which part of the eye is described as a 'convex' shape that focuses light rays to a point?
A.The Pupil
B.The Iris
C.The Lens
D.The Optic Nerve
- 7.
In a pitch-black room, if you turn on a torch and point it at a red ball, why does the ball look red?
A.The torch only produces red light.
B.The ball reflects the red part of the white light and absorbs the rest.
C.The ball creates its own red light when hit by any beam.
D.Our eyes add red color to objects in the dark.
- 8.
A student stands between two large plane mirrors that are perfectly parallel and facing each other. They notice a 'tunnel' of reflections that seem to go on forever. However, they observe that the reflections appear to get slightly dimmer and take on a faint green tint as they get 'deeper' into the distance. What is the primary scientific reason for this effect?
A.The speed of light decreases each time it reflects, causing the light to lose its original brightness.
B.The brain is unable to process images that are more than 10 meters away, so it creates a 'fading' illusion.
C.With every reflection, the mirror surface absorbs a small amount of light and the glass slightly filters the light colors.
D.Light rays from the further reflections are older and have lost their thermal energy as they traveled back and forth.
- 9.
A student looks at a rapidly spinning 'Newton’s Disc' which has all the colors of the rainbow. Even though the disc is made of distinct colored sections, the student perceives the disc as being white or light grey. Which explanation best describes why the brain 'sees' white instead of individual colors?
A.The lens of the eye rotates in the opposite direction to stabilize the image, causing the colors to cancel out.
B.The retina retains an image for a fraction of a second, causing the brain to overlap all the color signals into one perception.
C.The optic nerve can only transmit one color signal per second, so it chooses the average color of the light source.
D.When light reflects off a moving object, the different colors of the spectrum merge into a single wavelength before hitting the cornea.
- 10.
Which type of lens is found in the human eye, and what does it do to light rays?
A.A convex lens that converges (brings together) light rays
B.A concave lens that diverges (spreads out) light rays
C.A flat lens that reflects light rays back to the source
D.A square lens that turns light into electrical pulses
Download the worksheet for Light - How we see objects and the function of the eye to practice offline. It includes additional chapter-level practice questions.