The Doppler effect
Grade 11 Science Worksheet - Challenge Me
Circle the best answer, or write your answer on the line.
A 500 Hz train horn moves away at 25 m/s. With sound at 343.3 m/s in 20 °C air, what frequency does a listener behind it hear, to the nearest tenth, Ari?
A 600 Hz buzzer on a model train moves away at 10 m/s. With sound at 343.3 m/s in 20 °C air, what frequency does a listener behind it hear, to the nearest tenth, Bo?
A 250 Hz train horn moves away at 40 m/s. With sound at 343.3 m/s in 20 °C air, what frequency does a listener behind it hear, to the nearest tenth, Esme?
Two identical horns pass a listener. Horn X shifts by 10 Hz and horn Y by 30 Hz. Which is moving faster, Kira?
- They move at the same speed
- Horn X
- Horn Y
Which change would make a passing horn's Doppler shift bigger, Luz?
- A louder horn
- A longer train
- A faster train
Milo says a train's horn really changes its note as it passes a platform. Agree or disagree?
- Agree: the horn gets tired and drops
- Disagree: the note heard changes, not the horn's
- Agree: the driver changes the horn's note as it passes
Noah says a toy buzzer makes a higher note while it moves toward you. Agree or disagree?
- Agree: moving toward you makes the buzzer buzz faster
- Disagree: it makes the same note; you hear it higher
- Agree: buzzers change note when they move
Pia says the Doppler effect is the horn getting louder as it comes near. Agree or disagree?
- Disagree: it is a change in pitch
- Agree: loudness and pitch are the same
- Agree: nearer sounds are louder, and that is the effect
A radar speed sensor at a baseball game sends radio waves at a pitched ball. What can the shifted echoes show, Tala?
- How heavy the ball is
- How fast the ball is moving
- The color of the ball
What do astronomers learn from the redshift of distant galaxies, Zee?
- They are getting hotter
- They are moving away from us
- They are made of red rock