Waves：练习题

• a.\( 2.0 \, \text{Hz} \)
• b.\( 0.5 \, \text{Hz} \)
• c.\( 50 \, \text{Hz} \)
• d.\( 10 \, \text{Hz} \)

• a.Radio waves, infrared, visible light, X-rays
• b.Gamma rays, ultraviolet, visible light, radio waves
• c.Visible light, ultraviolet, X-rays, gamma rays
• d.Infrared, visible light, ultraviolet, gamma rays

• a.\( 0.25 \, \text{m/s} \)
• b.\( 1.0 \, \text{m/s} \)
• c.\( 100 \, \text{m/s} \)
• d.\( 4.0 \, \text{m/s} \)

• a.

  The direction of vibration of the particles is parallel to the direction of propagation of the wave.

• b.

  The wave consists of a series of crests and troughs that transfer matter along the path.

• c.

  The direction of vibration of the particles is at right angles to the direction of propagation of the wave.

• d.

  The particles move in a circular motion as the energy is transferred through the medium.

• a.

  It is a region where the speed of the sound wave is at its maximum.

• b.

  It is a region where the air pressure is lower because particles are spread further apart.

• c.

  It is a region where the particles are vibrating at a higher frequency.

• d.

  It is a region where the air pressure is higher because particles are closer together.

先自己写一遍答案，再对照解题步骤。