# physics

posted by .

At a distance of 30 m the noise from the engine of an jet has an intensity level of 130 dB.

At this level, you will be in pain and your ears will hurt. That's why this intensity is know as the "pain threshold".

How far do you have to be from a jet (total distance in meters), in order for the noise to drop down in intensity to 69 dB, a level comparable to that of a spoken conversation?

• physics -

A decrease in sound level by 61 dB amounts to a factor of 10^6.1 = 1.26^10^6 in sound power per area. To achieve this, you need to be sqrt(1.25*10^6) = 1122 times farther away. That corresonds to 30*1122 = 33,660 m away. (about 21 miles)

• physics -

thank you :)

## Similar Questions

1. ### physics - sound level

The source of a sound wave has a power of 2.50 µW. Assume it is a point source. (a) What is the intensity 6.70 m away?
2. ### Physics

1. How many nodes (counting nodes at the ends), are present in the displacement oscillations of an open-closed tube (oboe) that vibrates in its fourth harmonic?
3. ### Physics

At a distance of 30 m the noise from the engine of an jet has an intensity of 130 dB. At this level, you will be in pain and your ears will hurt. That's why this intensity is know as the "pain threshold". How far do you have to be …
4. ### Physics

1. What is the intensity of a sound at the pain level of 120 dB?
5. ### math

A loud speaker at a rock concert generates 102 W/m2 at 20m with a frequency of 1 kHz. Assume that the speaker spreads its intensity uniformly in all direction. (a) What is the sound level ( = ?
6. ### physics

The cabin noise level of the new Airbus 380 is 5 decibels lower than that of a 747 Jumbo Jet. By what factor does the noise intensity decrease?
7. ### physical

At a distance of 30 m the noise from the engine of an jet has an intensity level of 130 dB. At this level, you will be in pain and your ears will hurt. That's why this intensity is know as the "pain threshold". How far do you have …
8. ### Math

Formula given: The decibel (dB) scale for measuring loudness, d, is given by the formula d = 10 log base ten(I X 12 to the power of 12) where I is the intensity of sound in watts per square metre. a) Find the number of decibels of …
9. ### PreCalculas

The psychological sensation of loudness B is measured in decibels and is defined with reference to the intensity, , of a barely audible sound by the following equation. In this equation, I is the intensity of the sound in question. …
10. ### Physics

A decibel meter reads 130 dB at a certain position from a jet plane when one engine is turned on. a) What is the sound intensity at that position?

More Similar Questions