This is what I was wondering as well. I don't have a physics background but I thought terminal velocity was well below Mach 1. You fall at an increasing rate for a time and it eventually maxes out somewhere, You're not contiually accelerating right?
You will continue accelerating until the downward force is equal to the upward force. If there's little to no air resistance, then you will continue to accelerate for a very long time. Thus, he will probably continue to accelerate until he hits the lower levels of the stratosphere or upper levels of the troposphere.
are you sure thats possible? max falling speed is 9.8 meters per second and i just looked up and from what i find is mach 1 is at 298 meters per second
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Max falling ACCELERATION is 9.8 meters per second SQUARED. Throw wind resistance out and the guy's speed would continue increasing until he splattered on the Earth. You can figure this out (assuming I'm doing this right) by first figuring out the time it would take to hit Earth at 9.8 m/s^2, which is taking the square root of the quotient of 28,968.3 m (18 mi)/9.8 m/s^2, which is ~54 seconds. Multiply that by 9.8 m/s^2 and the speed should be ~530 m/s, or 1,184 mph.
Now when you account for wind resistance, the final speed will be much lower than 1184 mph because of something called terminal velocity, which occurs when wind resistance equals 9.8 m/s^2, effectively cancelling out gravity. You don't suddenly stop moving, you just stop accelerating - you continue falling at the same speed. Figuring out what terminal velocity is is above my pay grade, though, as it depends on what the factor for wind resistance is and whether the person is falling "standing up" or "spread eagle", as the person falling standing up's terminal velocity would be much higher than the person falling spread eagle - more surface area = more wind resistance = lower terminal velocity.
Chuck Lidell: I paint my toenails with pink and black polish. Problem is, I get more paint on my toes and on the carpet than on my nails. Any advice? Maria Sharapova: Don't you beat up other guys for a living? I don't know how to answer this.
You will continue accelerating until the downward force is equal to the upward force. If there's little to no air resistance, then you will continue to accelerate for a very long time. Thus, he will probably continue to accelerate until he hits the lower levels of the stratosphere or upper levels of the troposphere.
but by that logic if something was so massive you could fall until you reached just below light speed. There are a ton of factors, i doubt its possible to reach the speed of sound from falling to earth no matter how high up you are
but by that logic if something was so massive you could fall until you reached just below light speed. There are a ton of factors, i doubt its possible to reach the speed of sound from falling to earth no matter how high up you are
The only reason why a person wouldn't break the sound barrier falling is because of wind resistance causing terminal velocity well below the sound barrier. Somehow eliminate wind resistance (or reduce it) and that person would easily break the sound barrier.
Chuck Lidell: I paint my toenails with pink and black polish. Problem is, I get more paint on my toes and on the carpet than on my nails. Any advice? Maria Sharapova: Don't you beat up other guys for a living? I don't know how to answer this.
but by that logic if something was so massive you could fall until you reached just below light speed. There are a ton of factors, i doubt its possible to reach the speed of sound from falling to earth no matter how high up you are
Well, this guy hit 614 MPH and he jumped from 102,800 feet.
The guy that is planning on breaking the sound barrier will be jumping from 120,000 feet. Since he will be jumping from about 4 miles higher, he will probably have enough distance to hit the speed of sound before he runs into too much air resistance. I'm sure he can get that extra 154 MPH.
but by that logic if something was so massive you could fall until you reached just below light speed. There are a ton of factors, i doubt its possible to reach the speed of sound from falling to earth no matter how high up you are
I thought gravity effected everything the same, regardless of weight?
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I thought gravity effected everything the same, regardless of weight?
The force of gravity (weight) is a function of the mass of two objects and their distance apart. Weight as we know it is actually the force we feel as we stand on earth. Which is why things weigh differently on the moon and other planets, even though their mass remains unchanged.
Think of it like this:
Mass is a result of matter existing.
The feeling of weight is the result of two bodies of mass being in proximity to each other.
However more force does not cause objects to accelerate faster, as more massive objects require more force to accelerate at the same rate.
So to be 100% clear, gravity doesn't affect everything the same, but it does accelerate objects at the same speed regardless of mass (as mass increases, the force of gravity increases, but the amount of force to accelerate an object also increases). This is not accounting for air resistance.
Now terminal velocity enters when the force of resistance of the atmosphere equals the WEIGHT of an object. Weight (which is a force) is directly proportional to mass. So a more massive object (aerodynamics due to shape nonwithstanding) has a higher terminal velocity, but does NOT accelerate faster. It's additional mass allows it to reach higher speeds before air causes slowly causes it to stop accelerating.
Now as for the speed of light thing, if we take special relativity into account, an object's relative mass increases as it approaches the speed of light from a given reference frame. If the object's mass increases, the force required to continue accelerating it also increases. This puts a hard limit on speed of objects, because the force required to continue accelerating them faster increases as their relative velocity increases.
Anybody remember the first night game ? It was against Oklahoma I think in 1984 and the parachutist before the game came down and his parachute collapsed at the top of stadium level and he bounced off of the astro-turf surface about 40 feet in the air and died ?? We lost in final seconds 12-10 on field goal... it was his fault
Also, the speed of sound isn't constant; it varies with density, which in turn varies with altitude and temperature, and thus the speed of sound varies with altitude. Given the temperature and density profile of Earth's atmosphere, the speed of sound increases with altitude. So the speed of sound profile of the atmosphere works in this guy's favor.
NASA has a little speed of sound calculator based on an ideal gas analysis of the atmosphere...
Also, the speed of sound isn't constant; it varies with density, which in turn varies with altitude and temperature, and thus the speed of sound varies with altitude. Given the temperature and density profile of Earth's atmosphere, the speed of sound increases with altitude. So the speed of sound profile of the atmosphere works in this guy's favor.
NASA has a little speed of sound calculator based on an ideal gas analysis of the atmosphere...
I hate posts that take 10 minutes to research...
That seems really counter intuitive to me, that the speed of sound would increase in less dense air. I always understood that water has much higher speed of sound than the atmosphere because of the density difference, which would leave me to infer that at the top of the atmosphere it would be much less, but now I'm going to surmize that the extreme lack of resistance within the atmosphere allows the sound waves to propegate un-impeded at incredible speeds at the highest levels.
One thing in your post that I don't get... He would want the speed of sound to decrease, so he doesn't have to go as fast to break it, correct?
One thing in your post that I don't get... He would want the speed of sound to decrease, so he doesn't have to go as fast to break it, correct?
Well, after using the NASA speed of sound calculator to plot some points for speed of sound vs altitude (if the calculator is working correctly), my above statement is not correct for the entire fall. The profile helps him for awhile, but then works against him after a certain point.
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Originally Posted by Acylum 
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