 # QNS: how to solve more than two pulley problems and how to find accelaration of system contains pulley+wedge

13 years ago

Hi

The tips to be followed are:

Draw Big and clear Free Body Diagrams.

Indicate all the forces

Calculate the net force and hence calculate the net acceleration

The following procedure is recommended when dealing with problems involving
Newton’s laws:
• Draw a simple, neat diagram of the system.
• Isolate the object whose motion is being analyzed. Draw a free-body diagram
for this object. For systems containing more than one object, draw separate
free-body diagrams for each object. Do not include in the free-body diagram
forces exerted by the object on its surroundings. Establish convenient coordinate
axes for each object and find the components of the forces along
these axes.
• Apply Newton’s second law, F = ma, in component form. Check your dimensions
to make sure that all terms have units of force.
• Solve the component equations for the unknowns. Remember that you must
have as many independent equations as you have unknowns to obtain a
complete solution.
• Make sure your results are consistent with the free-body diagram. Also check
the predictions of your solutions for extreme values of the variables. By doing
so, you can often detect errors in your results.

Regards

Rajat