Frequency & the Doppler Effect

Question 1

What is frequency?

In relation to waves

Answer 1

The rate of repeating waves passing in a given time

Question 2

So, what’s the formulas for frequency?

Answer 2

• 1/T (period)
• 1 wavelength/ seconds

Question 3

What’s the relationship between frequency and wavelength?

Answer 3

They are inversely proportional
High f, shorter wavelength
Low f, longer wavelength

Question 4

So, when the frequency is high, what does that mean?

Answer 4

• More energy created
• Higher pitch
• Shorter wavelength (they are inversely proportional, remember? :>)

Question 5

So, when the frequency is low, what does that mean?

Answer 5

• Less energy created
• Lower pitch
• Longer wavelength (they are inversely proportional, remember? :>)

Question 6

What is the Doppler Effect?

Answer 6

Is when there’s a change in frequency of a wave depending how far or close a person is to the source

Question 7

Doppler Effect Continued

For example, how will the frequency of a sound wave change if plane is far away from you?

Answer 7

• Frequency be lower
• Pitch be lower
• Wavelength be longer

Question 8

Doppler Effect Continued

For example, how will the frequency of a sound wave change if a plane is closer to you?

Answer 8

• Frequency be higher
• Pitch be higher
• Wavelength be shorter

Question 9

Doppler Effect Continued

For example, how will the frequency of a visible light wave change if a star is far away from you?

Answer 9

• Frequency be lower
• light will look more red (red shift)

Question 10

Doppler Effect Continued

For example, how will the frequency of a visible light wave change if a star is closer to you?

Answer 10

• Frequency be higher
• light will look more blue (blue shift)