Press the power push button the left front corner the interface

By definition torque	( τ)	is a vector product of distance and applied force	F

Magnitude of torque τ is

(2) τ = r Fsinϕ

τ = r	fsinϕ

maintain the static equilibrium? To solve this problem, we can use the conditions of rotational static equilibrium.

When a body is in rotational static equilibrium like in Figure 2, the sum of all the torques,

Setup
1. Set up the strut system shown as Figure 2. The steel rod is fixed on the lab table.

The super pulley on the bent rod is fixed in the hole on top of the steel rod by a thumb screw. Two weights ( W andW ) 1 2 added on the weight hanger will be hung on two different string loops on the strut.

6. Open “Lab 121 Rotational Equilibrium” file in “Physics 102A Lab Experiments” folder on Desktop.

7. Press “Zero” button located on the force sensor without hanging the pendulum.

weight of the aluminum rod of the strut which is written on it.

2. In order to keep θ2 = 0°, θ1 has to be a certain value. Measure and record.

5. Compare your experimental results with the calculations.

3.2 The strut in a position with an angle ( 2 / 0°) tilted up
2. You can decide the angle for	θ2
3.3 The strut in position with an angle θ2 / 0° tilted down 1. Keep all the conditions ( L1 L2 L3 L, WandW ) 1 2 same as in Part I except for the
2. You can decide the angle for	θ2

Data Tables
Table I
Weight of strut (AI rod) = 0.11683kg , L = 0.61cm


θ2 = 3 0 °	W 2 = 0.15kg

Tension Calculated: 6.475

T=		2 r	sin (90−θ ) 2
	L 3sin (θ ) 1

In part one the strut being supported by the cord was oriented in a way so that it made a right angle with, and was therefore perpendicular to the pivot. For part two, the strut was oriented to an angle of thirty degrees above the horizontal. During part three this angle was changed to thirty degrees below the horizontal. What remained the same for each of the three parts was the presence of weights located at distances L1 and L2 over the strut, along with the distance L3 at which the cord was attached. For each part, a tension sensor was present in order to calculate the experimental value for the tension in the cord. The theoretical value would be computed knowing that the sum of the torques in the clockwise and counterclockwise directions had to be equal, and therefore have a net value of zero. Of course, torque is the value of a force computed over a distance. In this case, it was necessary to use components of forces, due to the differing angles.

By verifying that the percent error value between experimentally and theoretically derived values for the force of tension in the cord were relatively low, we were then able to confirm that the objectives of the lab had been sufficiently completed.