Light and Sound

Which of the waves needs medium to propagate?

• infrared

• sound wave

• radio waves

• visible light

Arrange the following colors of light in order of decreasing energy: red, blue, orange, green.

• blue, green, orange, red

• green, blue, red, orange

• orange, red, blue, green

• red, orange, green, blue

Which of the following behaviors of light causes light to be dispersed?

• absorption

• reflection

• refraction

• scattering

Which of the following explains why violet appears at the bottom of the rainbow?

• Violet has the highest speed in a medium among the other visible-light colors.

• Violet bends the most in a medium among the other colors.

• Violet has the longest wavelength.

• Violet has the lowest energy.

Which of the following is true about the effect of the elastic property of a material on the speed of sound?

• The lesser the elasticity, the greater the speed of sound.

• The lesser the elasticity, the lesser the speed of sound.

• Elasticity has a lesser influence on the speed of sound than the density of an object.

• Elastic properties of a material do not affect the speed of sound.

The higher the mass of an object, the higher the speed of sound.

• true

• false

Sound travels faster in brass than in hydrogen.

• true

• false

temperature greatly affects the speed of sound in air.

• true

• false

The white-colored wall reflects all the colors of the visible light.

• true

• false

Green leaves absorb completely green light.

• true

• false