A2L Item 041
- Description: Determine the ratio of masses for a pulley system to remain at rest.
- Goal: Reasoning qualitatively.
- Source: UMPERG
- Keywords: Dynamics, Mechanics, Reasoning, Tension
The question for students:
Consider the arrangement of pulleys and masses shown below. The masses of the pulleys are small. Ignore friction.
For what relationship of the masses would the masses remain at rest?
- m/M > 2
- m/M = 2
- m/M = 1.5
- m/M = 1
- m/M = 0.5
- m/M = 0.25
- m/M < 0.25
- none of the above
- Cannot be determined
Commentary for teachers:
Answer
(5); This problem can be reasoned although it is easy enough to solve algebraically. The problem is useful for demonstrating the value of free body diagrams for reasoning.