IMO Practice Test — Light & Shadows
6 Questions • 12 min • Olympiad level
12:00
Question 1 of 6
hard
In a dark cinema we can still see the screen because the screen sends ___ to our eyes.
Sound
Light
Heat
Air
Explanation: We see the screen because light reaches our eyes.
Question 2 of 6
hard
Two torches shining on one object from different sides can make…
A mirror
No shadow ever
A rainbow
Two shadows
Explanation: Each light makes its own shadow, so two form.
Question 3 of 6
hard
Moving a torch closer to an object makes its shadow on the wall…
Smaller
Bigger
Disappear
Colourful
Explanation: A closer light makes a larger shadow.
Question 4 of 6
hard
The word AMBULANCE is written backwards on the front of vans so that drivers ahead read it correctly in their…
Window
Mirror
Shadow
Map
Explanation: A mirror flips it back to normal for the driver ahead.
Question 5 of 6
medium
Why can we see the Moon shining at night if it makes no light?
It has bulbs
It burns gas
It reflects sunlight to us
It is a star
Explanation: The Moon shines by reflecting the Sun's light.
Question 6 of 6
hard
Coloured cellophane is transparent but tinted; looking through red cellophane makes the world look…
Reddish
Black
Invisible
Louder
Explanation: Tinted transparent sheets colour the light passing through.