The Doppler Effect
How relative motion changes observed frequency
|
Video Instruction showmethephysics.com
Doppler Effect
School Blocks YouTube? Use the file below.
St.
Mary's U. A bicyclist with a siren audibly demonstrates the Doppler
effect (turn your speakers up!)
[ HTML5 ]
G. Doppler Effect – variation in the observed frequency of a wave when there is relative motion between the source of the wave and the receiver
Doppler Effect
V = 14 m/s
Doppler Effect
V = 18 m/s
Stationary Ambulance? How can you tell?
To the left
The Doppler
Effect II
The Doppler Effect
[ HTML5 ]
[ HTML5 ]
Review - The crack of a whip
|
|||||||||||
NYSSLS Reading Passage · Waves
How Doppler Radar Decodes the Sky
Open Reading Passage → Regents Practice Version →Check Your Understanding
5 quick questions — pick an answer to see if you’re right.
1. The Doppler effect is
2. A train blowing its horn moves toward you. Compared with the horn's actual pitch, the pitch you hear is
3. An ambulance with its siren on drives away from you. What do you hear?
4. As a car with a siren speeds past, does the frequency produced by the siren itself change?
5. Doppler radar bounces microwaves off a rainstorm. What does the frequency shift of the echo reveal?
A Passing Ambulance
An ambulance siren emits sound at a steady frequency of 700 Hz. A pedestrian stands on the sidewalk as the ambulance approaches, passes, and moves away.
Which statement describes the frequency the pedestrian hears?
▶ Want a challenge? Open 6 more Regents-style questions (harder · mixed formats)
Challenge score: 0 / 6
C1. A student makes the following claim.
Place a check mark in either the Support or Refute box. Justify your response using a mathematical relationship.
C2. What does the paramedic riding in the ambulance hear?
C3. The ambulance is parked with its siren on. The speed of sound in the air is 343 m/s. Substitute numerical values into a mathematical representation that can be used to determine the wavelength of the siren’s sound. Then calculate the wavelength.
C4. Compared with when the ambulance is parked, place a check mark in three boxes to indicate the quantities that are different for the sound reaching the pedestrian while the ambulance approaches.
C5. Police radar sends microwaves toward a car and measures the frequency of the reflected waves. What does a larger frequency shift indicate?
C6. The ambulance is parked with its siren on. A cyclist rides toward the ambulance at a steady speed. Predict whether the cyclist hears a frequency higher than, lower than, or equal to 700 Hz, and explain your prediction.