Hello everyone! This is the third problem of the competition discussed in this thread. Please read the rules there for details on scoring and the prize.

Rules/Procedures:

- Do NOT post your answers or work in this thread, please PM me your answer and work. You will receive TWO chances to answer correctly.
- Within the PM include: Your name, status as a high schooler or recent graduate (yes/no), and whether you had any help answering the question.
- Websites, textbooks, other people, physics professors/teachers, etc. are NOT allowed as resources! You are free to use these resources and submit an answer to see if you were correct (learning new concepts is great!), but you will be disqualified from earning points for any questions you do this for.

**Problem 3:**

Suppose that you have an Atwood’s machine (with a massless, frictionless pulley and strings) that connects two masses, M1 and M2. M1 has a mass of 5KG while M2’s mass is unknown. Answer the following questions based on this information, using -9.81m/s^2 for g.

A: What value of M2 will result in M1 accelerating at 0m/s^2?

B: Assume that the mass of M2 has changed from part A. If the acceleration of mass 1 and 2, A, is equal to 6.7 m/s^2(Positive for M1, Negative for M2), what is the tension, T, above mass 1 equal to?

C: Assume that the initial acceleration, A1, of M1 and M2 is 0m/s^2. After some time, a mass is added to M2 which results in the acceleration of -8 m/s^2 from the perspective of M2. What is the mass that was added to M2?

D: Describe a scenario where the magnitude of acceleration experienced by M1 would exceed 9.8m/s^2, assuming that M2 was not connected to the Atwood’s machine.You are free to move the machine to any location you feel, accelerate it, change the mass of M1, etc.

Answers are due MIDNIGHT(eastern) this Sunday!