Solving Atwood's Machine: Find Forces & Acceleration

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To solve Atwood's Machine, apply Newton's laws of motion to analyze the forces acting on two connected masses. A free body diagram for each mass reveals the forces: weight (mg) and tension (T). The acceleration (a) of both masses can be calculated using the formula a = (m2g - m1g)/(m1+m2), while the tension in the string is given by T = (m1m2g)/(m1+m2). Experimental verification can be achieved by measuring acceleration and tension with a force sensor and comparing these values to the calculated results. This approach ensures a comprehensive understanding of the dynamics involved in Atwood's Machine.
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The machine shown in the figure below can be used to give you a good feel
for forces. Assuming a massless, frictionless pulley and a massless string,
calculate the magnitude of the acceleration on both bodies and the tension in
the string T.

http://img110.exs.cx/my.php?loc=img110&image=d9kq.jpg

Find the force exerted by the Atwood's machine on the hanger which the
pulley is attached to while the blocks accelerate. Neglect the mass of the
pulley.

The pulley in Atwood machine above is given an upward acceleration a. Find
the acceleration of each mass and the tension in the string that connects
them. How can you test your result

No idea with these questions. Any help would be appreciated. Thanks :smile:
 
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Solving Atwood's Machine involves applying the principles of Newton's laws of motion. In this machine, there are two masses connected by a string that passes over a frictionless and massless pulley. The first step in solving this problem is to draw a free body diagram for each mass, showing all the forces acting on them. In this case, there are two forces acting on each mass - the weight (mg) and the tension in the string (T).

Now, using Newton's second law (F=ma), we can write an equation for each mass:

For the first mass (m1):
T - m1g = m1a

For the second mass (m2):
m2g - T = m2a

Since the pulley is massless, we can assume that the tension in the string (T) is the same on both sides. We can also assume that the acceleration of the two masses is the same, as they are connected by a string. Therefore, we can combine the two equations and solve for the acceleration (a):

T - m1g = m1a
m2g - T = m2a

Adding the two equations, we get:
m2g - m1g = (m1+m2)a

Solving for a, we get:
a = (m2g - m1g)/(m1+m2)

This is the acceleration of both masses. To find the tension in the string (T), we can substitute this value of acceleration in any of the two equations we wrote earlier. For example, using the first equation:
T - m1g = m1a
T - m1g = m1[(m2g - m1g)/(m1+m2)]
T = (m1m2g)/(m1+m2)

Therefore, the tension in the string is:
T = (m1m2g)/(m1+m2)

To test our result, we can perform a simple experiment using this Atwood's machine. We can vary the masses and measure the acceleration and tension in the string using a force sensor. We can then compare our calculated values with the measured values to see if they match. If there is a significant difference, we can check for any errors in our calculations and make necessary adjustments. This way, we can verify the accuracy of our solution.
 
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