# Thread: Physics ( Multiple choices question)

1. ## Physics ( Multiple choices question)

How do i find which force creates the largest moment about the pivot?

What is the Pole on the point of the solenoid with an arrow pointing towards it drawn by me as induced by the other circuit?

Any help is appreciated. I am looking for the reasoning behind not only the answer!! thx

2. The torque is $rF\sin\theta$ where r is the distance from the hinge to P, F is the magnitude of the force and $\theta$ is the angle between the beam and the force.

In the second problem, you know the initial air volume, pressure (atmospheric plus the excess mercury) and temperature. Using the Ideal gas law, you can find the amount of air. Then, using the new volume, you can find the new pressure.