HW

Solve for the practical lab problems completed in class - do the "left torques" equal the "right torques"?  Don't forget about the mass of the meter stick.

Reconsider the scaffold problem.  You have a 4-m long scaffold (60 kg), supported by cables at the extreme ends.  Two workers are standing on it:  Jack (75 kg, 1-m from the left) and Jill (65 kg, 2.5-m from the left).  What is the tension in each cable?

Have a look at the ladder problem in the student guide.  Note that there is an error in the text.  Under rotational equilibrium, it should actually say:

Rotational equilibrium:

W (L/2 cos q) = F (L sin q)

Note the change from L to L/2 --- this is because the weight of the ladder acts through its center of gravity.

Try to make sense of the ladder problem and solve the one in the homework if you can.  I'll post a solution before class meets again.