Solving for Acceleration in an Incline Plane Problem: m1=4.50kg, m2=2.80kg

AI Thread Summary
The discussion centers on calculating the acceleration of two blocks connected by a cord over a pulley, with one block on a frictionless incline and the other hanging vertically. The block on the incline has a mass of 4.50 kg and is at a 30° angle, while the hanging block has a mass of 2.80 kg. Participants emphasize the importance of recognizing that both blocks share the same magnitude of acceleration but in opposite directions. A key point raised is the need to analyze the forces acting on each block separately using free body diagrams. The original poster acknowledges previous errors and plans to reattempt the problem with this new understanding.
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Homework Statement



A block of mass m1 = 4.50 kg on a frictionless inclined plane of angle 30.0° is connected by a cord over a massless, frictionless pulley to a second block of mass m2 = 2.80 kg hanging vertically.

What is the magnitude of the acceleration of each block?



Homework Equations





The Attempt at a Solution



I have attached two of my many attempts. I think the second attempt is closer because I realized that since the blocks are connected that they have the same magnitude of acceleration but just different directions. Both of these answers are wrong along with the many others I have submitted. Some help and/or hints would be great. Thanks.
 

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The force acting on the mass m1 via mass m2 is the tension T in the rope and it is only equal to m_1*g when nothing moves. The mass m_1 is accelerating so T - m_1*g = m_1*a, T is not equal to m_1.

I think it helps to draw a separate free body diagram for each mass.
 

Attachments

  • mass on plane027.jpg
    mass on plane027.jpg
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Ok thanks that makes sense. I'll try the problem again tomorrow.
 
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