Pressure Required to propel something a long distance

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In summary, pressure is needed to send a person flying, around 155psi, and to shatter a bone, around 2,000psi.
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OriginalH1h
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I am making this (hopefully in the correct forum) because I started debating propulsion about objects and the like. The main two questions I want to have answered if at all possible are as follows:

How much pressure would be needed to send a person flying?

How much pressure is needed to shatter a bone, or at least crack it?

Examples to better explain the questions: (I will specify statistics like height, weight, and other factors)

* For sending a person flying, a person around 5'10", 154 lbs, with his arm outstretched to its full extent. from the point of an inch away from the palm, an explosion is created in that bit of air, like a jet engine, the outward facing force shoots away from the person, but there is an inward for like the jet engine, is actually a rocket. Like pressure pushes the rocket out the way it is pointed, but there is still force coming out the opposite way. For that opposite, excess force, what would the pressure have to be, to send the above stated man back about 10 feet. The excess force doesn't hit his entire body, it is centered on his palm, but still send him backwards.

* Same person, same outstretched arm, same variables, same thing happens, but what ends up happening to the bones in his arm leading to his shoulder blade specifically? To add onto that though as another side example, a new variable. The man's bones have the same density and strength as military grade steel, but are easier to warp with heat, and now, there is an extreme amount of heat involved (around 200 degrees Fahrenheit)

(This may sound like I am going to attempt to harm someone or myself by experimenting, I would like to clarify that that is not the case, I am just interested in this type of stuff from time to time)
 
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Pushing a person's hand is a very inefficient and typically impractical way of getting the person to fly 10 feet.
So let's say we apply that force closer to the center of gravity for the person - say the lower rib cage while the person has their legs retracted.

Let's say that we are applying this force with a small rocket that is pushing against a circular spot on that persons rib cage that is exactly 1 square inch in area. And let's say that the person is face down - so the rocket is pushing him straight up.

In this configuration, the rocket will need to push 154 pounds to overcome gravity and fully support the weight of that person. Since this force is applied to a 1 square inch, the pressure would be 154 psi.

But you want the person to go "flying". Technically, at 155psi, the person would begin to accelerate upwards - eventually reaching a height of 10 feet. So 155psi would do it.

Similarly, maintaining a 155psi pressure on that person would eventually result in that person reaching an altitude of hundreds or thousands of feet. Then just turn off the rocket and you will have plenty of broken bones.

I know this isn't exactly what you were expecting in the way of a response. But perhaps you can be more specific in your scenario - it's pretty hard to address it the way you posed the problem.
 
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.Scott said:
Pushing a person's hand is a very inefficient and typically impractical way of getting the person to fly 10 feet.
So let's say we apply that force closer to the center of gravity for the person - say the lower rib cage while the person has their legs retracted.

Let's say that we are applying this force with a small rocket that is pushing against a circular spot on that persons rib cage that is exactly 1 square inch in area. And let's say that the person is face down - so the rocket is pushing him straight up.

In this configuration, the rocket will need to push 154 pounds to overcome gravity and fully support the weight of that person. Since this force is applied to a 1 square inch, the pressure would be 154 psi.

But you want the person to go "flying". Technically, at 155psi, the person would begin to accelerate upwards - eventually reaching a height of 10 feet. So 155psi would do it.

Similarly, maintaining a 155psi pressure on that person would eventually result in that person reaching an altitude of hundreds or thousands of feet. Then just turn off the rocket and you will have plenty of broken bones.

I know this isn't exactly what you were expecting in the way of a response. But perhaps you can be more specific in your scenario - it's pretty hard to address it the way you posed the problem.
No this is a great response it answered another question that I was building in my mind.
 

Related to Pressure Required to propel something a long distance

1. What is pressure?

Pressure is defined as the force per unit area. It is a measure of how much force is applied to a certain area.

2. How does pressure relate to propulsion?

In order to propel something a long distance, a force must be applied to overcome the resistance or inertia of the object. This force is often created by increasing the pressure behind the object, pushing it forward.

3. What factors affect the pressure required to propel something a long distance?

The pressure required to propel something a long distance is affected by several factors, including the mass of the object, the distance it needs to travel, the medium it is traveling through, and the amount of resistance or friction it encounters.

4. How can pressure be increased to propel something a long distance?

Pressure can be increased by using a larger force or by decreasing the area over which the force is applied. For example, using a smaller nozzle to release a fluid will increase the pressure and therefore increase the propelling force.

5. What are some applications of using pressure for propulsion?

Pressure is commonly used in various forms of propulsion, such as in rockets, jet engines, and water propulsion systems. It is also used in everyday objects like water guns and aerosol cans.

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