Your friend is belching the alphabet. Where you are standing, a distance of 2 meters from...
You stand 5 meters away from two machines. One machine operates at a sound intensity level that is 50 dB at your location. The other machine operates at a sound intensity level of 70 dB at your location. What sound intensity level do you hear (measure in dB) when both machines are turned on?
A bagpiper is playing in the middle of the quad. To a person standing 20 m away, the sound intensity level of the bagpiper is 90.6 dB. 17. [2pt] What is sound intensity level 24 m away from the bagpiper? (Assume that the bagpiper is a point source of spherical waves.) 18. [2pt] What's the intensity of the sound of the bagpiper 24 m away? 19. [2pt] If the sound intensity level of one bagpiper is 90.6 dB twenty meters...
A bagpiper is playing in the middle of the quad. To a person standing 20 m away, the sound intensity level of the bagpiper is 87.8 dB. 17. What is sound intensity level 25.5 m away from the bagpiper? (Assume that the bagpiper is a point source of spherical waves.) 18. [2pt] What's the intensity of the sound of the bagpiper 25.5 m away? 19. [2pt] If the sound intensity level of one bagpiper is 87.8 dB twenty meters away,...
A person standing a certain distance from ten identical loudspeakers is hearing a sound level intensity of 123 dB. What sound level intensity would this person hear if four are turned off?
5. The threshold of human hearing at a frequency of 1.0 kHz is usually defined to be exactly 0 dB (for purposes of significant figures, consider this to be an exact, pure number). A research study shows that if exposed to 95 dB of a sound source for a long time, the threshold of hearing will shift upward to 32 dB. This accounts for why it is hard to hear normal conversations for some time after leaving a loud concert....
A 25 MW jet engine produces a sound level of 120 dB, the threshold of pain, at 100 m from the engine. (Recall that the threshold of human hearing is 1 x 10-12 W/m2.) (a) What portion of the jet engine power is lost in producing this sound? (b) You are at your quiet summer house (ambient sound level is 40 dB) and you can just hear the sound of the same jet engine at the airport. How far away...
Dolphins emit sound bursts that range in frequency from 1 Hz to 120 kHz. Say that a dolphin is using a sound burst consisting of these frequencies as a form of sonar, like bats. Let the burst last for a time interval of 10 ms, after which it listens for 100 ms. Say that the logarithmic intensity (loudness) of the dolphin's sound is 50 dB as measured at 1 m away. Dolphins can hear sounds that are 2 dB below...
5. By how many decibels do you reduce the sound intensity level due to a source of sound if you double your distance from it? Assume that the waves expand spherically. dB 6. The sound in a classroom is 63000 times as intense as the minimum threshold of hearing. What is the intensity level of this sound in decibels? dB
At 10:02 am local time on August 27, 1883, the Krakatoa volcano exploded. This volcanic eruption supposedly generated the loudest sound ever heard on Earth. Measurements at the time placed the peak sound level of 165 dB at a distance of 40 miles from the eruption! This large transient sound level will break your ear drums and corresponds to an increase in air pressure of 2.5 inches of mercury. (a) What is the intensity (I) of the eruption sound at...
You stand 30 m from a large speaker at a concert, and the intensity of the sound you hear from that speaker is 4×10−2 W/m2 . How much power is the speaker emitting? What is the intensity of the sound from the speaker at a distance of 60 m ? The pain threshold for humans is a sound intensity level of about 120dB. At what distance from this speaker would the sound be painful?