How do you find to torque if force is applied over entire levl

In summary, to calculate the torque exerted by water on a rectangular hatch on the side of a box, you will need to calculate the total force exerted by the water on the hatch by integrating over the surface, breaking it up into strips of constant force at constant depth. The torque can then be calculated by integrating the force over the hatch surface, taking into account the distance from the reference point or axis. This will involve expressing the surface as thin rectangular area elements.
  • #1
bjon-07
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Lets say you have a box that is filled with water. One of the side of the box contains retangular hatch. How much torques does the water exert on the hatch?


Do you just calculate the total force that the water is exerting on the square are of the rectangular hatch. Force=Pressure X Area ?
 
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  • #2
bjon-07 said:
Lets say you have a box that is filled with water. One of the side of the box contains retangular hatch. How much torques does the water exert on the hatch?


Do you just calculate the total force that the water is exerting on the square are of the rectangular hatch. Force=Pressure X Area ?

Pressure depends on depth, so the force is not uniform. You well have to integrate over the surface, breaking it up into strips of constant force at constant depth. I assume you want the torque calculated about the top or the bottom of the hatch. The answer depends on the rotation axis you choose.
 
  • #3
I found the total force that a fluid will expert on a wall using intergration,


since force is equal to pressure X times area and pressures = density x gravity x height = interal of PGH dh


which turned out to be 1/2(density)(gravity)(width of the wall)(height of the wall)^2

now that I have the total force exerted on the object, is there a way to find the total toruqe exerted on the object. Let's make the hing of the box be the folcrum
 
  • #4
bjon-07 said:
I found the total force that a fluid will expert on a wall using intergration,


since force is equal to pressure X times area and pressures = density x gravity x height = interal of PGH dh


which turned out to be 1/2(density)(gravity)(width of the wall)(height of the wall)^2

now that I have the total force exerted on the object, is there a way to find the total toruqe exerted on the object. Let's make the hing of the box be the folcrum
HINT:
Since fluid pressure ⊥ Hatch Surface:

[tex] 1: \ \ \ \ \textsf{Torque} \ \, = \, \ \int_{Hatch} r \, P \ dA [/tex]

where "r" is the distance of Area Element "dA" from the Reference Point or Axis, and "P" is the fluid pressure on Area Element "dA". Both "r"and "P" will be functions of Area Element "dA" position on the Hatch Surface. You'll likely express "dA" in terms of thin rectangular area elements over the Hatch Surface.


~~
 
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1. How do you define torque?

Torque is a measure of a force's tendency to cause an object to rotate about an axis. It is calculated by multiplying the force applied by the distance from the axis of rotation to the point where the force is applied.

2. What is the equation for calculating torque?

The equation for torque is T = F x r, where T is torque, F is the applied force, and r is the distance from the axis of rotation to the point where the force is applied.

3. How is torque different from force?

Torque and force are related, but they are not the same. Force is a linear push or pull on an object, while torque is a rotational force. Torque is also dependent on the distance from the axis of rotation, while force is not.

4. How do you find torque if the force is applied over the entire level?

If the force is applied over the entire level, you would need to calculate the torque at each point where the force is applied and then sum them together to find the total torque. This can be done by multiplying the force at each point by the distance from the axis of rotation to that point, and then adding all of these values together.

5. How is torque measured?

Torque is measured in units of newton-meters (Nm) in the SI system or pound-feet (lb-ft) in the imperial system. A torque wrench is commonly used to measure torque by applying a known force and measuring the distance from the axis of rotation to the point of application.

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