Your work on torques has been received. Scroll down through the document to see any comments I might have inserted, and my final comment at the end.
Your optional message or comment:
Positions of the three points of application, lengths of systems B, A and C (left to right), the forces in Newtons exerted by those systems, description of the reference point:
5, 7.4, 11.4
9.3, 9.3, 9.7
1.78, 1.55, 1.9
From left end of rod.
Used the graphs from the previous calibration experiment.
The middle force was exerted by a doubled rubber band system; you have to include the forces exerted by both of those rubber bands.
Net force and net force as a percent of the sum of the magnitudes of all forces:
-2.13
Moment arms for rubber band systems B and C
7, 4
Lengths in cm of force vectors in 4 cm to 1 N scale drawing, distances from the fulcrum to points B and C.
7.0, 6.5, 7.9
7,4
Torque produced by B, torque produced by C:
-7.6
+12.46
Net torque, net torque as percent of the sum of the magnitudes of the torques:
+4.86
.06
I added the positive and negative torques. I did not get 0 as I should have. I then calculated the net torque as a percentage of the lengths of all the bands.
Forces, distances from equilibrium and torques exerted by A, B, C, D:
The sum of the vertical forces on the rod, and your discussion of the extent to which your picture fails to accurately describe the forces:
Net torque for given picture; your discussion of whether this figure could be accurate for a stationary rod:
For first setup: Sum of torques for your setup; magnitude of resultant and sum of magnitudes of forces; magnitude of resultant as percent of sum of magnitudes of forces; magnitude of resultant torque, sum of magnitudes of torques, magnitude of resultant torque as percent of the sum of the magnitudes:
For second setup: Sum of torques for your setup; magnitude of resultant and sum of magnitudes of forces; magnitude of resultant as percent of sum of magnitudes of forces; magnitude of resultant torque, sum of magnitudes of torques, magnitude of resultant torque as percent of the sum of the magnitudes:
In the second setup, were the forces all parallel to one another?
Estimated angles of the four forces; short discussion of accuracy of estimates.
x and y coordinates of both ends of each rubber band, in cm
Lengths and forces exerted systems B, A and C:.
Sines and cosines of systems B, A and C:
Magnitude, angle with horizontal and angle in the plane for each force:
x and y components of sketch, x and y components of force from sketch components, x and y components from magnitude, sine and cosine (lines in order B, A, C):
Sum of x components, ideal sum, how close are you to the ideal; then the same for y components.
Distance of the point of action from that of the leftmost force, component perpendicular to the rod, and torque for each force:
Sum of torques, ideal sum, how close are you to the ideal.
How long did it take you to complete this experiment?
Optional additional comments and/or questions:
See my note and, if necessary, please submit your data and your revised conclusions.