How To Determine Newton Meter Force

In summary, to determine the Newton meter force requirement and rpm's for an electrical motor in this example, you will need to calculate the RPM by dividing the distance the mass must travel by the circumference of the shaft and calculate the torque by multiplying the radius of the shaft by the force needed to lift the weight. The requirements needed for this application are unclear.
  • #1
Mr. Nice Guy
2
0
Hello!

How do you calculate or determine Newton meter force requirement and rpm's for an electrical motor in the following example:

A device that utilizes a shaft that is 2 inches in diameter and 6 feet length. It needs to be able to lift 10 pounds and distance of 7 feet in 6 seconds. I need to know the formulas to make these calculations and the requirements needed for this application?

Thanks in advance for any assistance!

Mr. Nice Guy.
 
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  • #2
RPM can be found by dividing the distance the mass must travel by the circumference of the shaft. The torque will be equal to the radius of the shaft times the force to lift the weight. I am unsure what you are asking for in the second part of your request.
 
  • #3



Hello Mr. Nice Guy,

Thank you for your question. To determine the Newton meter force requirement for an electrical motor, we need to first understand the concept of torque. Torque is the rotational equivalent of force and is measured in Newton meters (Nm). It is calculated by multiplying force (in Newtons) by the distance from the axis of rotation (in meters). So, in this case, we need to calculate the torque required to lift 10 pounds (4.54 kilograms) at a distance of 7 feet (2.13 meters) in 6 seconds.

The formula for torque is T = F x d, where T is torque, F is force, and d is distance. Plugging in the values, we get:

T = (4.54 kg)(9.8 m/s^2)(2.13 m)

T = 95.8 Nm

This is the torque required to lift the weight. Now, to determine the rpm's for the motor, we need to use the formula:

ω = (2πN)/60, where ω is angular velocity (in radians per second), N is the rpm, and 60 is the number of seconds in a minute.

We know the distance (2.13 meters) and time (6 seconds) for one revolution, so we can calculate the angular velocity as:

ω = (2π)(1 revolution)/(6 seconds)

ω = 1.05 rad/s

Now, we can plug this value into our torque formula to solve for the required rpm:

T = (I)(α), where I is the moment of inertia and α is the angular acceleration. Since we know the torque (95.8 Nm) and the angular velocity (1.05 rad/s), we can rearrange the formula to solve for the moment of inertia:

I = T/α

I = (95.8 Nm)/(1.05 rad/s^2)

I = 91.24 kgm^2

Finally, we can use this moment of inertia to solve for the required rpm:

N = ω/(2π)(I)

N = (1.05 rad/s)/(2π)(91.24 kgm^2)

N = 0.006 rpm

Therefore, the required rpm for the motor is approximately 0.006 rpm. However, keep in mind that this is a simplified calculation and there may be other factors to consider, such as friction
 

1. What is a Newton meter?

A Newton meter (Nm) is a unit of measurement for force, also known as torque. It is a combination of the Newton unit of force and the meter unit of length, and is often used to measure the force required to rotate an object around an axis.

2. How do you determine Newton meter force?

To determine Newton meter force, you need to multiply the force (in Newtons) by the distance from the axis of rotation (in meters). This calculation is represented by the formula Nm = N x m. For example, if a force of 10 Newtons is applied at a distance of 2 meters from the axis of rotation, the resulting torque would be 20 Nm.

3. What are some common applications of Newton meter force?

Newton meter force is commonly used in engineering and physics to measure the force required to rotate objects, such as screws, bolts, and gears. It is also used in the automotive industry to measure the torque produced by engines, and in construction to measure the force required to tighten nuts and bolts.

4. What is the difference between Newton meter force and Newton meter energy?

Newton meter force is a measure of rotational force, while Newton meter energy is a measure of work or energy. Force is the application of a push or pull on an object, while energy is the ability of an object to do work. They have the same unit of measurement, but they measure different aspects of an object's movement.

5. How is Newton meter force related to other units of force?

Newton meter force is equivalent to a unit of work or energy, known as the joule (J). Additionally, one Nm is also equal to one kilogram-meter squared per second squared (kg-m^2/s^2), which is the unit for measuring work, energy, and torque in the International System of Units (SI).

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