Rigid Bodies and Free Body Diagrams (w pulley)

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SUMMARY

The discussion focuses on analyzing a system involving two blocks connected by a string over a pulley, with specific parameters: block m1 has a mass of 1.87 kg, block m2 has a mass of 5.84 kg, and the pulley is a solid disk with a radius of 0.180 m and mass of 12.7 kg. The coefficient of kinetic friction for both blocks is 0.357. The key tasks are to determine the acceleration of the blocks and the tensions in the string using free-body diagrams and Newton's second law, while incorporating the effects of torque on the pulley.

PREREQUISITES
  • Understanding of Newton's laws of motion
  • Knowledge of free-body diagrams
  • Familiarity with torque and rotational dynamics
  • Concept of friction and its calculation using normal force
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  • Study the application of Newton's second law to rotational systems
  • Learn how to derive equations for tension in a pulley system
  • Explore the relationship between linear and angular acceleration in connected systems
  • Investigate the effects of friction on inclined planes and pulley systems
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Physics students, mechanical engineers, and anyone studying dynamics and rotational motion in systems involving pulleys and inclined planes.

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Question: "A block of mass m1 = 1.87 kg and a block of mass m2 = 5.84 kg are connected by a massless string over a pulley in the shape of a solid disk having radius R = 0.180m and mass M = 12.7 kg. These blocks are allowed to move on a fixed block-wedge of angle 31.4 degrees as in the figure. The coefficient of kinetic friction is .357 for both blocks.

A) Using free-body diagrams of both blocks and of the pulley, determine the acceleration of the two blocks.

B) Determine the tensions in the string on both sides of the pulley.
"
Diagram

BLOCK(m1) Pulley
__________________\
\\
\\\\
\\\\\BLOCK (m2)
\\\\\
ANGLE\\\\
_________________________\\

My basic question here is how I factor in the pulley. I'm assuming I need to incorporate torques with the pulley and convert them to forces such that I can find a F(net)=ma for each block.

Block m1 WORK DONE:
X: F(net) = T1(Tension of string) - F(friction)
Y: F(net) = -m1g + N = 0

Block m2 WORK DONE:
X: F(net) = m2gsin(Theta) - T2(String) - F(friction)
Note: X is directed along the slope of the ramp.
Y: F(net) = -m2gcos(Theta) + N = 0
Perpindicular to ramp.

Thats as far as I got. Any help is appreciated.
 
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So far, so good. Write F(friction) in terms of the normal force and the coefficient of friction.

Treat the pulley as a rotating disk with the two tensions exerting torques on it.

Now apply Newton's 2nd law to all three objects. Be sure to incorporate the system constraint relating the motion of all three: Since they are attached by a string, the linear acceleration of both masses must be the same (in magnitude). What's the relationship between the linear acceleration of the masses and the angular acceleration of the pulley?
 

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