- 70 I T 1. [1pt] A professor of mass m = 51 kg is seated on a light harness connected to a rope and pulley system as shown. The professor's feet touch a uniform plank of mass mplank 12 kg which is supported by a hinge at the wall. A mass M in a light bucket is suspended from the right end of the plank. The professor is a distance = 2.60 m from the hinge; the plank has length L = 4.50 m. L plank Answer true or false to the statements below; e.g., if the first one is true and the rest are false, enter TFFFF. i. The weight of the plank leads to a counter-clockwise torque on the plank, taken about the hinge. ii. If M> 0, the right end of the plank will accelerate downward for some values of M. iii. If the plank remains horizontal, the concept of torque is not important in order to calculate the tension in the rope. iv. If the plank remains horizontal, the force of the professor on the plank is equal to the weight of the professor. v. If M = 0, the professor and the plank are always in static equilibrium, as long as L>l. Answer: Submit All Answers Last Answer: FTFTF Not yet correct, tries 1/15 2. [1pt] For the values given above, find the tension in the rope if M is zero. Answer: Submit All Answers Last Answer: ON Not yet correct, tries 1/15 3. [1pt] What is the minimum value of M needed to make the professor just lose contact with the plank? Answer: Submit All Answers Last Answer: 51 kg Not yet correct, tries 1/15