Electromagnetic spectrum

How are the colours of the rainbow formed?

• from the sun hitting water

• From light hitting objects

• Through different wavelengths of refracted light

When does a rainbow occur in nature?

• after a snowstorm

• after a rainstorm, when the sun comes out

Which colours of the rainbow have the longest wavelength?

• violet

• indigo

• red

Rainbows are just straight lines across the sky?

• no, they are full circle

• no, they are a half crescent

white light is a mixture of

• six colours

• seven colours

• eigth colours

Which of the following statements about an image in a plane mirror is incorrect?

• The image is laterally inverted

• The image is the same distance behind the mirror as the object is in front.

• The image is real

• The image is the same size as the object

Which of the following statements about the reflection of light is incorrect?

• The angle of incidence is equal to the angle of reflection

• The normal is perpendicular to the mirror surface

• Increasing the angle of incidence increases the angle of reflection

• The normal, incident ray, reflected ray lie in different planes

What is the angle of refraction in a glass block of refractive index 1.52 if the angle of incidence is 32°?

• 20°

• 54°

• 23°

• 60°

Light is incident in air on a glass surface at the critical angle. What is the angle of refraction?

• 90°

• 45°

• 0°

• 180°

What is the critical angle for plastic of refractive index 1.42?

• 55°

• 45°

• 65°

• 35°