Physical Science Unit 3

• The speed of light is slowed as it enters a solid because the molecules are blocked from passing through the medium

• Both types of waves speed up as they pass from one phase into another because the molecules spread out to help make the wave move faster.

• The speed of sound increases as it passes through a solid because the molecules are closest together in this phase of matter and the sound can pass along fastest.

• Both types of waves slow down as they pass from one phase into another because the molecules come close together which slows the wave down due to interference.

The speed of sound increases as the density of the medium increases. Through which substance would sound waves travel the slowest?

• gelatin

• water

• wood

• air

How does the bat know whether it is moving toward or away from the insect it is trying to catch?

• The bat uses sound echoes to locate an insect, then the bat uses the thermal outline of the insect to find and catch it.

• The bat uses sound echoes to locate large objects like trees or buildings; the bat uses thermal imaging to locate insects for food.

• The bat uses sound echoes to create an image of the environment in which the bat is flying; the bat also listens for the sound made by insects as it uses its wings to fly.

• The bat uses sound echoes to locate the insect; the bat can detect the small changes in sound wavelength that indicate if it is moving toward or away from the insect.

• Light travels fastest through high density media, slower through media of lower density, and slowest through media with the lowest densities. Light travels at different speeds through high density media depending on the material.

• Light travels fastest through media with the lowest densities, slower through media with higher densities, and slowest through media with the highest densities. Light travels at different speeds through high density media depending on the material

• Light travels slower through low density media than it does through high density media but faster through media with slightly higher densities than it does through low density media. The material making up the medium does not affect the speed of light.

• Light travels faster through low density media than it does through media with higher densities but slower through these media with higher densities than it does through the media with the highest densities. The material making up the medium does not affect the speed of light.

• 1 – Diffraction 2 – Refraction 3 – Reflection 4 – Interference

• 1 – Interference 2 – Reflection 3 – Refraction 4 – Diffraction

• 1 – Refraction 2 – Reflection 3 – Interference 4 – Diffraction

• 1 – Diffraction 2 – Reflection 3 – Refraction 4 – Interference

A Physical Science class was learning about the Doppler effect and used the given model to explain the changes in sound waves as the object producing the sound moves to the right.

• The circles representing the sound waves are spread apart on the left showing that the wave has a short wavelength and a high frequency, and they are close together on the right showing that the wave has a large wavelength and a low frequency. B

• The circles representing the sound waves are spread apart on the left showing that the wave has a large wavelength and a high frequency, and they are close together on the right showing that the wave has a short wavelength and a low frequency.

• The circles representing the sound waves are spread apart on the left showing that the wave has a large wavelength and a low frequency, and they are close together on the right showing that the wave has a short wavelength and a high frequency.

• . The circles representing the sound waves are spread apart on the left showing that the wave has a short wavelength and a low frequency, and they are close together on the right showing that the wave has a large wavelength and a high frequency.

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Mr. James pointed a loudspeaker to a wall at an angle. At this time, Gabrielle was elected as the listener. She then faced the wall so that she could look at the point on the wall at which the speaker was directed. Gabrielle then announced to the class that she perceived the sound as if it was coming from a “virtual” loudspeaker on the opposite side of the wall, as shown.

Which of the following BEST describes the reason for Gabrielle's observation?

• Sound bounced off a reflective wall.

• Sound bounced off a refractive wall.

• Sound bounced off a diffractive wall.

• . Sound bounces off an interfering wall.

How can the behavior of waves in the models BEST be described?

• 1 – Diffraction

  2 – Refraction

  3 – Reflection

  4 – Interference

• 1 – Interference

  2 – Reflection

  3 – Refraction

  4 – Diffraction

• 1 – Refraction

  2 – Reflection

  3 – Interference

  4 – Diffraction

• 1 – Diffraction

  2 – Reflection

  3 – Refraction

  4 – Interference

• As the density of gases and solids increases, the speed of sound increases.

• As the density of gases and solids increases, the speed of sound decrease

• The speed of sound decreases when the density of gases increases and increases when the density of solids increases.

• The speed of sound increases when the density of gases increases and decreases when the density of solids increases.