2,007 reputation
835
bio website
location New York, United States
age
visits member for 4 years, 1 month
seen 2 days ago

I am an electrical engineer who is easily distracted by physics.


Oct
12
awarded  Popular Question
Sep
30
awarded  Popular Question
Sep
25
comment Would wearing clothing that is black on the inside and white on the outside keep you cooler?
@mukunda: Yes, a white trashbag and nothing else. That will make you cool no matter what the season.
Sep
24
awarded  Autobiographer
Sep
18
revised Why does water make a sound when it is disturbed?
added 177 characters in body
Sep
4
awarded  Popular Question
Aug
11
revised Doppler effect of sound waves
added 96 characters in body
Aug
11
revised Is work done by sound wave on air particles?
added 52 characters in body
Aug
7
revised Amount of energy required to hover.
formatting of math and units (Mgv/2 is in watts, which are power, not energy)
Aug
7
comment Amount of energy required to hover.
So this is why human-powered helicopters have enormous surface area: Using a large surface area to move the same mass rate of air at a lower velocity requires lower power levels for the same payload weight.
Aug
7
suggested approved edit on Amount of energy required to hover.
Aug
4
comment Picking up audio using high speed video?
Why a high-speed camera? Can't they get the same information from a single-cell photosensor and a telescope?
Jul
21
awarded  Nice Question
Jul
15
revised Why does my wife's skin buzz when she's using her laptop?
added 80 characters in body
Jul
12
comment Is it possible to create an audible sound source in mid air by intersecting ultrasonic sound beams?
@ChrisMueller: No, the beat frequency envelope is a pressure variation at 2 frequencies. The envelope is not a frequency component, unless you demodulate it non-linearly. Mixing them together doesn't produce any new tones at 1 kHz (unless you're using the radio engineer definition of "mixing", which is nonlinear). Try playing a tone you can't hear out of one speaker (17 kHz), and another tone you can't hear out of another speaker (18 kHz) at the same time. You still won't hear anything, because you're just summing 2 inaudible frequencies.
Jul
11
comment Is it possible to create an audible sound source in mid air by intersecting ultrasonic sound beams?
@ChrisMueller Yes, it's true. Mixing (summing) two sources produces a beat frequency envelope in the loudness of the signal, but there is no tone present at that beat frequency. Linear systems cannot produce new frequencies. If you sum 30 kHz and 30.1 kHz, there will be nothing audible in the mix. If you sum them and then distort the mixture, audible tones at 1 kHz, 2 kHz, etc. will be produced through intermodulation distortion. Same difference between a combination tone and a power chord.
Jul
2
awarded  Curious
Jun
26
comment Would wearing clothing that is black on the inside and white on the outside keep you cooler?
"would a black lining inside a white robe help in cooling the body by removing infrared radiation faster?" There's no way to tell, since the visible color has no relationship to the infrared reflectance/transmittance/absorption.
Jun
26
revised Would wearing clothing that is black on the inside and white on the outside keep you cooler?
added 20 characters in body
Jun
26
revised Would wearing clothing that is black on the inside and white on the outside keep you cooler?
added 20 characters in body