# Newton’s law of motion for rotation clarification

1. Sep 24, 2014

### Luchekv

Hey guys,
I'm trying to work through a question but the solution we have been given is extremely vague. I can't seem to figure out what any of the values such as Beta or Tmax are. If I knew how to work those two out, I'm sure I'd be fine from there...

See attached image.

Thanks in advance

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2. Sep 24, 2014

### Staff: Mentor

It looks like T is the thrust from each motor, so $T_{max}$ would be the maximum thrust. And from Newton's 2nd law for rotation, Torque = I*alpha, you should be able to deduce what Beta is.

3. Sep 24, 2014

### Luchekv

Well seeing as T1 is Tmax...(8N) I get Beta as 888.889...Not sure if it means both T1 and T2. Also what would be the value of t in the second equation at the bottom?

4. Sep 24, 2014

### Staff: Mentor

Careful. What must the total thrust be so as to maintain the height? Also, what value of d are you using?

The purpose of that equation is to solve for $t_1$.

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