Is the unit of torque Nm or Nm/°?

In summary, the unit of torque is typically represented as Nm, but it can also be represented as (Nm)/°. This is because angles do not have physical units and can be expressed as ratios of lengths. However, the magnitude of torque is independent of any angle, so both representations are correct.
  • #1
lmelbye
1
0
Hello everybody

Normally you say that the unit of torque is Nm but could also be (Nm)/°.?

I'm claiming this because of the fact that you normally do not give radians any unit, and that is why you just write Nm and not (Nm)/rad.

SI claims that: "torque may be thought of as the cross product of force and distance, suggesting the unit Newton metre, or it may be thought of as energy per angle, suggesting the unit joule per radian"
http://www.bipm.org/en/si/si_brochure/chapter2/2-2/2-2-2.html [Broken]

We have:

Force*distance=energy =>
[Nm] = [J] which leads to:
[J/rad] = [Nm]/[rad]

So, am I right when I say that unit of torque could be Nm as well as (Nm)/°?
 
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  • #2
No. Degrees are considered to be units. The magnitude of a torque or moment is independent of any angle.
 
  • #3
lmelbye said:
So, am I right when I say that unit of torque could be Nm as well as (Nm)/°?
Angles don't have physical units. Radians is just a ratio of two lengths. Degrees is that ratio multiplied by some constant factor.
 

1. What is the difference between Nm and Nm/°?

Nm (newton-meter) is a unit of torque, which is the measure of the turning force of an object. Nm/° (newton-meter per degree) is a unit of angular torque, which measures the torque applied to an object in relation to its rotational angle. In other words, Nm/° takes into account the angle of rotation, while Nm does not.

2. Which unit is more commonly used in scientific calculations?

Nm is more commonly used in scientific calculations, as it is a simpler and more general unit of torque. However, Nm/° is more commonly used in engineering and mechanical applications, where precise measurements of rotational force are needed.

3. How are Nm and Nm/° related?

Nm and Nm/° are related by a conversion factor of 1 Nm = 1 Nm/°. This means that they are equivalent units, but Nm/° takes into account the angle of rotation while Nm does not.

4. Can Nm and Nm/° be used interchangeably?

No, Nm and Nm/° cannot be used interchangeably. They represent different units of torque and have different applications. Nm is used for general torque calculations, while Nm/° is used for more specific angular torque calculations.

5. How do I convert between Nm and Nm/°?

To convert from Nm to Nm/°, simply multiply the value in Nm by the angle of rotation in degrees. To convert from Nm/° to Nm, divide the value in Nm/° by the angle of rotation in degrees. For example, 10 Nm/° is equivalent to 10 Nm x 1° = 10 Nm, and 10 Nm is equivalent to 10 Nm/° ÷ 1° = 10 Nm/°.

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