# Physics

posted by .

1. A train whistle has a frequency of 1000 Hz. If the train is speeding
at a velocity of 60 km/h past a stationary railroad crossing
attendant, what is the apparent frequency a) as the train approaches him, b) as it moves away from him?
Assume speed of sound to be 350 m/s.

2. A second train is approaching the first train (above) with a speed of
60 km/h. Obtain the frequency of the whistle of the first as heard by
the engineer of the second train.

3. Sound is reflected by a screen moving with a speed 20 km/h toward
the source and observer. If the frequency of the source is 450 khz,
what is the apparent frequency of the reflected sound?

Help me solve these questions

## Similar Questions

1. ### Physics doppler effect

A person standing close to a railroad crossing hears the whistle of an approaching train. He notes that the pitch of the whistle drops as the train passes by and moves away from the crossing. The frequency of the approaching whistle …
2. ### physics

A train is moving parallel to a highway with a constant speed of 16.0 m/s. A car is traveling in the same direction as the train with a speed of 36.0 m/s. The car horn sounds at a frequency of 504 Hz, and the train whistle sounds at …
3. ### Physics

A person standing close to a railroad crossing hears the whistle of an approaching train. He notes that the pitch of the whistle drops as the train passes by and moves away from the crossing. The frequency of the distant approaching …
4. ### Physics

A train blows its horn as it approaches a crossing. The train engineer observes a frequency of 118 Hz and a stationary observer observes a frequency of 122 Hz. What is the speed of the train?
5. ### Physics

A train is moving at a speed of 30 m/s toward a stationary observer at a train station. The train whistle blows with an actual frequency of 336 Hz. What horn frequency is heard by the engineer (riding on the train)?
6. ### Physics

The observed frequency of a train whistle is 513Hz as it approaches a stationary observer and is 432Hz as it recedes. Find the speed of the train
7. ### Physics

train moving with speed 72 km h−1 emits a whistle of frequency 600 Hz. A person is standing stationary on the platform. Calculate the frequency heard by the person if the train (i) approaches and (ii) recedes away from the listener.
8. ### physics

A train moving with speed 72 km h−1 emits a whistle of frequency 600 Hz. A person is standing stationary on the platform. Calculate the frequency heard by the person if the train (i) approaches and (ii) recedes away from the …
9. ### Physics

A train blows its horn as it approaches a crossing. A.) if the train engineer observes a frequency of 125Hz and a stationary observer at the crossing observes a frequency of 132Hz, what is the speed of the train?
10. ### Physics

You are sitting on a train that is about to drive into a tunnel that is at the base of a large cliff. Just before entering the tunnel, the train blows its whistle, which has a frequency of 600 Hz. (a) What frequency do you hear from …

More Similar Questions