Light: A Wave and a Particle, Physical Science

What type of wave propagates parallel to the direction of energy transfer?

• transverse wave

• mechanical wave

• longitudinal wave

• electromagnetic wave

Answer explanation

In a longitudinal wave, the particles of the medium move parallel to the direction of the wave's energy transfer.

What is carried by a wave as it travels?

• color

• energy

• light

• particle

Answer explanation

Energy is carried by a wave as it travels, transferring from one location to another without necessarily transferring matter.

Waves can be classified into groups. Which of the following statements give the correct basis of classifying waves?

I. based on the direction and the amount of energy exerted to create the wave

II. based on their ability or inability to transmit energy through a vacuum

III. based on the direction of wave propagation relative to the direction of energy transfer

IV. based on the ability to change the direction of the wave relative to the direction of energy transfer

• I and II

• I and III

• II and III

• III and IV

Answer explanation

Waves can indeed be classified based on their ability or inability to transmit energy through a vacuum (II) and the direction of wave propagation relative to the direction of energy transfer (III).

Which of the following is not an electromagnetic wave?

• microwave

• visible light

• X-ray

• sound wave

Answer explanation

Sound waves are mechanical waves that require a medium to travel through, unlike electromagnetic waves (such as microwaves, visible light, and X-rays) which can travel through vacuum.

Which does not belong to the group?

• sound wave

• jump rope wave

• water wave

• radio wave

Answer explanation

Jump rope wave is not a natural phenomenon like sound waves, water waves, and radio waves. It's a specific action performed with a rope, so it doesn't belong to the group of naturally occurring waves.

Which of the following statements is not true?

• All EM waves are transverse waves.

• A sound wave is an example of a mechanical wave.

• All mechanical waves are longitudinal waves.

• All waves are transverse and longitudinal waves.

Answer explanation

This statement is false because not all waves exhibit both transverse and longitudinal characteristics. Some waves, like sound waves, are purely longitudinal, while others, like light waves, are purely transverse.

Visible light wave can be classified as ___________.

I. longitudinal wave

II. electromagnetic wave

III. transverse wave

IV. mechanical wave

• I and II

• II and IV

• I and III

• II and III

Answer explanation

Visible light waves are electromagnetic waves because they consist of oscillating electric and magnetic fields that propagate through space. These waves are transverse in nature because the oscillations of the electric and magnetic fields occur perpendicular to the direction of wave propagation.

How are sound wave and stadium wave similar?

• They both need medium to travel on.

• They both do not need medium to travel on.

• They are both transverse waves.

• They are both longitudinal waves.

Answer explanation

Both sound waves and stadium waves require a medium to travel through. Sound waves propagate through materials such as air, water, or solids, while the stadium wave involves the sequential standing and sitting of spectators in a stadium, propagating through the movement of people.

Which is an example of a wave that is both transverse and longitudinal?

• surface wave

• sound wave

• light wave

• stadium wave

Answer explanation

Surface waves, such as ocean waves, exhibit characteristics of both transverse and longitudinal waves as they involve a combination of motion perpendicular to the direction of propagation (transverse) and motion parallel to the direction of propagation (longitudinal).

How are mechanical waves different from electromagnetic waves?

• Mechanical waves are produced by vibration of charged particles while EM waves are produced on a medium.

• Mechanical waves need a medium to travel on while EM waves do not.

• Mechanical waves are transverse while EM waves longitudinal.

• Mechanical waves do not need medium to travel on while EM waves do.

Answer explanation

Mechanical waves, such as sound waves, require a medium (solid, liquid, or gas) to propagate, while electromagnetic waves, such as light waves, can propagate through vacuum, which means they do not require a medium to travel through.