(adsbygoogle = window.adsbygoogle || []).push({}); 1. The problem statement, all variables and given/known data

A beam is supported only at one point, called the pivot point, as shown in the diagram. A block with mass m1 sits at the left end of the beam, a distance L1 from the pivot point. A block with mass m2 sits at the right end of the beam, a distance L2 from the pivot point. L2 > L1. Calculate all torques about the pivot point, remembering that positive is anti-clockwise.

Select Yes, No, Less than, Equal to, or Cannot tell.

- Given particular values of L1, L2, and m1, is it always possible to choose m2 such that the masses have no angular acceleration?
- If m1 * L2 = m2 * L1, is there a negative torque?
- For m1 = m2, does the angular acceleration depend only on L1 / L2 ? (If it depends on the actual values of L1 and L2, put 'no'.)
- If m1 * L1 = m2 * L2, will the masses have an angular acceleration?

2. Relevant equations

Torque = Force*L

3. The attempt at a solution

- For the first statement, since L2 is always greater than L1 by a certain ratio, if M2 is less than M1 by that same ratio, then there would be no torque, and thus no angular acceleration. However, I'm not certain my thought process is correct.
- Since the two lengths are flipped, and no exact masses are given, there is no way to determine if this statement is true or false.
- I'm really stuck on this one.... I put no, since the torque is calculated from the sum of the each individual torque, not the product nor the quotient.
- If the two torques are the same, then the beam wouldn't move, and thus would have no angular acceleration.

Please help me and thanks in advance.

**Physics Forums | Science Articles, Homework Help, Discussion**

Join Physics Forums Today!

The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

# Homework Help: Pivot point of a beam and torque

**Physics Forums | Science Articles, Homework Help, Discussion**