Ttorque angular acceleration units check

AI Thread Summary
The discussion centers on calculating the angular acceleration of a hypothetical wheel with a moment of inertia of 1 lb*ft² when a torque of 1 ft/lb is applied for 1 second. Participants emphasize the importance of distinguishing between pound-mass and pound-force in U.S. customary units. The initial condition of the wheel being at rest is confirmed, and it is noted that this affects the calculations. The conversation highlights the need to determine the resulting acceleration from the applied force. Ultimately, the participants seek clarity on whether the wheel achieves a rotation of 1 r.p.s. after the torque is applied.
mstram
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Given :

A (hypothetical) wheel with a m.o.i. of 1 lb*ft^2

Radius of wheel = 1.9099 inches, therefore circumference of wheel = 1 foot

The wheel is at rest, i.e. zero rotation speed.

A torque of 1 ft/lb is applied for 1 second

Is the result a rotation of 1 r.p.s. (60 r.p.m.) ?

thx
Mike
 
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mstram said:
Given :

A (hypothetical) wheel with a m.o.i. of 1 lb*ft^2

Radius of wheel = 1.9099 inches, therefore circumference of wheel = 1 foot

A torque of 1 ft/lb is applied for 1 second

Is the result a rotation of 1 r.p.s. (60 r.p.m.) ?

thx
Mike
If you are working in the system of U.S. customary units then you should carefully distinguish between pound-mass and pound-force. I see at least two problems with your result. Let's start with the easier one: What acceleration is produced when one pound force acts on one pound mass?
 
Sorry, I meant to write the initial rotation of the wheel is zero (at rest).

Does that make a difference ?
 
mstram said:
Sorry, I meant to write the initial rotation of the wheel is zero (at rest).
Does that make a difference ?
It would make a difference. But It seemed clear that we were to assume a start from rest anyway.

Again, what acceleration would you expect from a one pound mass subject to a one pound force?
 
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