Request How far can sound travel?
I'm a writer that wrote herself a bullshit math problem that's over her paygrade(nothing) because I'm stupid so I decided to do the time honored tradition of asking reddit for help. So, assuming standard everything, how far can a 70 decibel sound wave from 30,000 to 40,000hz travel/be picked up by a receiver tuned to that frequency?
https://redd.it/1vwoled
@TheyDidTheMath
I'm a writer that wrote herself a bullshit math problem that's over her paygrade(nothing) because I'm stupid so I decided to do the time honored tradition of asking reddit for help. So, assuming standard everything, how far can a 70 decibel sound wave from 30,000 to 40,000hz travel/be picked up by a receiver tuned to that frequency?
https://redd.it/1vwoled
@TheyDidTheMath
Reddit
From the theydidthemath community on Reddit
Explore this post and more from the theydidthemath community
This media is not supported in your browser
VIEW IN TELEGRAM
[request] how tall is this ice wall? Human at the front of the boat for reference.
https://redd.it/1vwp31m
@TheyDidTheMath
https://redd.it/1vwp31m
@TheyDidTheMath
[Request] How dense and fast would a sword need to be to cut the head off a statue?
https://redd.it/1vwuhqp
@TheyDidTheMath
https://redd.it/1vwuhqp
@TheyDidTheMath
[Request] What would it take to give the entire Baltic Way a static shock, like in a school science experiment?
https://redd.it/1vwv43a
@TheyDidTheMath
https://redd.it/1vwv43a
@TheyDidTheMath
[Request] How much weight are you actually lifting on the pull-down side? Assume 80kg person using it.
https://redd.it/1vx5761
@TheyDidTheMath
https://redd.it/1vx5761
@TheyDidTheMath
[Request] Presuming this was for a 200-pound, six-foot male. How much time would it take for the hourglass to empty?
https://redd.it/1vx7wrh
@TheyDidTheMath
https://redd.it/1vx7wrh
@TheyDidTheMath
This media is not supported in your browser
VIEW IN TELEGRAM
[Request] Disregarding the compression to upload, at 8gbps, can mumbo actually upload raw 32k streams?
https://redd.it/1vxfmez
@TheyDidTheMath
https://redd.it/1vxfmez
@TheyDidTheMath
[Request] What is the shortest flight time possible (with timezones)
https://redd.it/1vxje8m
@TheyDidTheMath
https://redd.it/1vxje8m
@TheyDidTheMath
[Request] A disease affects 1% of people. With a 99% sensitive and 99% specific test, what is the exact probability a positive test means you are actually sick?
/r/VouchPick/comments/1vwrw77/a_test_has_99_sensitivity_and_99_specificity_you/
https://redd.it/1vxfs6b
@TheyDidTheMath
/r/VouchPick/comments/1vwrw77/a_test_has_99_sensitivity_and_99_specificity_you/
https://redd.it/1vxfs6b
@TheyDidTheMath
Reddit
From the theydidthemath community on Reddit: [Request] A disease affects 1% of people. With a 99% sensitive and 99% specific test…
Posted by LivingSupermarket344 - 12 votes and 25 comments
[Request] approximately how many Roman soldiers in this painting?
https://redd.it/1vxs629
@TheyDidTheMath
https://redd.it/1vxs629
@TheyDidTheMath
[Request] Why does this circle approximation still give 4 instead of pi?
https://redd.it/1vxtynk
@TheyDidTheMath
https://redd.it/1vxtynk
@TheyDidTheMath
Self Which travels faster? Air molecule or a bullet?
(Is it the right way to do it?)
The higher the temperature the faster molecules travel. In fact temperature can be defined by how fast molecules move. It's called thermal velocity.
Assuming a bullet is shot at 500m/s - 1300m/s, at which temperature does the air move faster? For air, we need to account for it being a mixture of nitrogen and oxygen.
Here is the equation for the speed in 3D space: v = √(8(K_B T)/m).
k_B is Bolzmann constant
T is the temperature in Kelvin.
m is the mean mass of an air particle.
We are looking for a T that gives v = 1300m/s.
K_B = 1.380649 e\^-23 K\^-1 J
m = n1*m_N2 + n2*m_O2 = [0.78*(2*14) 0.21*(2*16)\] * 1.672 e\^-27 kg = 4.777 e\^-26 kg
T = mv\^2 / 8 K_B = (4.777 e\^-26 [kg\]) 1300\^2 [m\^2/s\^2\]/ 8 1.380649 e\^-23 [K\^-1 J\] = 731 K = 458°C
For v =500 m/s, T = 108 K = -165°C.
Therefore air particles in room temperature on average are in the range but not as fast as the fastest bullets.
https://redd.it/1vxvozd
@TheyDidTheMath
(Is it the right way to do it?)
The higher the temperature the faster molecules travel. In fact temperature can be defined by how fast molecules move. It's called thermal velocity.
Assuming a bullet is shot at 500m/s - 1300m/s, at which temperature does the air move faster? For air, we need to account for it being a mixture of nitrogen and oxygen.
Here is the equation for the speed in 3D space: v = √(8(K_B T)/m).
k_B is Bolzmann constant
T is the temperature in Kelvin.
m is the mean mass of an air particle.
We are looking for a T that gives v = 1300m/s.
K_B = 1.380649 e\^-23 K\^-1 J
m = n1*m_N2 + n2*m_O2 = [0.78*(2*14) 0.21*(2*16)\] * 1.672 e\^-27 kg = 4.777 e\^-26 kg
T = mv\^2 / 8 K_B = (4.777 e\^-26 [kg\]) 1300\^2 [m\^2/s\^2\]/ 8 1.380649 e\^-23 [K\^-1 J\] = 731 K = 458°C
For v =500 m/s, T = 108 K = -165°C.
Therefore air particles in room temperature on average are in the range but not as fast as the fastest bullets.
https://redd.it/1vxvozd
@TheyDidTheMath
Wikipedia
Thermal velocity
typical velocity of the thermal motion of particles
This media is not supported in your browser
VIEW IN TELEGRAM
[Request] how fast is the cannonball moving and how much force does it strike Frank with?
https://redd.it/1vxwby5
@TheyDidTheMath
https://redd.it/1vxwby5
@TheyDidTheMath