- #1
Davidllerenav
- 424
- 14
Homework Statement
Given the picture:
- Make the free body diagrams of each body and the pulley. Remember that there are two different strings therefore there are two different tensions.
- Assuming that the mobile of mass M starts from rest and has a displacement D at a time t, and the bodywith mass m falls a height h at the same time, calculate the accelerations of the mobile a_1 and the body a_2 (Note: Use only cinematics).
- Assuming that the accelerations of the bodies are known, calculate the tensions in the strings, and the coefficient of friction between the mobile and the table. Despise the pulley mass and friction between pulleys and rope.
Homework Equations
Kinematics equations.
The Attempt at a Solution
Ok, So for the first one, I made the diagrams of each body like this. Is it correct?
For the second one, it says that the mobile of mass M starts from rest, so ##v_0M=0##, and ##v_M=at##. The displacement would be ##D=\frac{at^2}{2}+D_0##, so the acceleration would be ##a_1= \frac{V_M}{t} = \frac{2D}{t^2} + D_0##.
Now, for the body with mass m I set the inicial speed as ##0##, so ##v_0m=0##, thus ##V_m=-gt##. The Fall would be ##F=h-\frac{gt^2}{2}. Thus ##g= -\frac{v_m}{t} = h-\frac{2F}{t^2}. Am I correct?
For the third one, I don't know what to do. Pleas help me.