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Help Physics - Pulleys

Xantheri

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Pulleys introduce a possible source of error because of their possible friction. Given that they are a source of error, why are the pulleys used at all? What is the function of the pulleys
 
Pulleys are used in various mechanical systems because they offer mechanical advantage, allowing a smaller force to be exerted over a longer distance to move a heavier load. This is because pulleys redirect the force applied to them, which increases the effective force available to lift a load.

Although they can introduce friction and thus decrease efficiency, the benefits that they bring are often significant enough to outweigh the costs. Pulleys are commonly used in many types of machinery, including cranes, elevators, and even simple machines like block and tackle systems.

It is important to note that the amount of friction introduced by a pulley system can be minimized by choosing pulleys with low friction coefficients and by using lubricants. Additionally, proper alignment and tensioning of the cables or ropes used with the pulleys can also help to reduce friction.

Overall, pulleys are a crucial component in many mechanical systems and are used because they offer significant mechanical advantage, often making it possible to lift or move heavy objects that would otherwise be impossible to move with human strength alone.
 
Suppose the same masses are used for a force table experiment as were used in Part 1, but each pulley is moved 1800 so that the 0.100 kg mass acts at 2000, and the 0.200 kg mass acts at 2700. What is the magnitude of the resultant in this case? How does it compare to the resultant in Part 1?
 
In this case, the direction of the forces will be different because the pulleys have been moved. The new direction of the 0.100 kg mass will be 20 degrees and the new direction of the 0.200 kg mass will be 270 + 20 = 290 degrees.

To calculate the magnitude of the resultant force, we need to use the same method as in Part 1. We can draw a diagram with vectors representing the forces acting on the masses and use trigonometry to find the magnitude and direction of the resultant force.

Using this method, we find that the magnitude of the resultant force in this case is approximately 0.27 N. This is smaller than the magnitude of the resultant force in Part 1, which was approximately 0.36 N.

The reason for this difference is that the new directions of the forces are closer together (70 degrees apart) than they were in Part 1 (120 degrees apart). This means that there is less of a difference between the horizontal and vertical components of the forces, which results in a smaller magnitude of the resultant force.
 
Two forces are applied to the ring of a force table, one at an angle of 20.00, and the other at an angle of 80.00.
Regardless of the magnitudes of the forces, describe which quadrant the resultant and equilibrant can be located.
 
Since the two forces are not opposite and not collinear, the ring will experience a net force and will move in a certain direction. The direction of the resultant force will depend on the magnitudes and directions of the two forces.

To find the direction of the resultant force, we can use the vector addition of the two forces. We can draw the two forces as vectors originating from the center of the force table and add them using the parallelogram method. The diagonal of the parallelogram will represent the resultant force and its direction will be the direction of the net force.

Since one force is at an angle of 20.00 and the other at an angle of 80.00, the two forces will be separated by 60 degrees. This means that the parallelogram method will result in a rhombus shape, with the diagonal representing the resultant force.

The direction of the equilibrant force will be opposite to the direction of the resultant force. Since the resultant force will be located in a certain quadrant, the equilibrant force will be located in the opposite quadrant.

Therefore, depending on the magnitudes and directions of the two forces, the resultant force can be located in any of the four quadrants, and the equilibrant force will be located in the opposite quadrant.
 
Can you paraphrase this? “Since the two forces were located in the first quadrant, the resultant force is located in the first quadrant. The equilibrant force can be located in the third quadrant since it is the vertical of the first quadrant and the equilibrant force opposes the resultant force and possesses the same magnitude but a different direction.”
 
As both forces were situated in the first quadrant, the resultant force also lies in the first quadrant. Conversely, the equilibrant force can be found in the third quadrant as it is opposite in direction to the resultant force and has equivalent magnitude but a dissimilar direction since it's the vertical of the first quadrant.
 
Can you paraphrase this?
“Pulleys are used in various mechanical systems because they offer mechanical advantage, allowing a smaller force to be exerted over a longer distance to move a heavier load. This is because pulleys redirect the force applied to them, which increases the effective force available to lift a load. Although they can introduce friction and thus decrease efficiency, the benefits that they bring are often significant enough to outweigh the costs.”
 
Pulleys are employed in diverse mechanical systems due to their ability to provide mechanical advantage. This means that a smaller force can be applied over a longer distance to move a heavier load. They achieve this by redirecting the force applied to them, which increases the effective force available to lift the load. Even though they can result in friction and reduce efficiency, the advantages they offer are usually substantial enough to surpass the drawbacks.
 
Two forces, one of magnitude 2 N and the other of magnitude 3 N, are applied to the ring of a force table. The directions of both forces are unknown. Which best describes the limitations on R, the resultant? Explain carefully the basis for your answer. (a) R≤5 N (b) 2 N≤R≤3 N (c) R≥3 N (d) 1 N≤R≤5 N (e) R≤2 N
 
The force table problem involves finding the resultant of two or more forces acting on a ring. The resultant is the net force, which is the single force that has the same effect as the original forces. The magnitude and direction of the resultant are determined by the vector addition of the original forces.

In this problem, the two forces have magnitudes of 2 N and 3 N, and their directions are unknown. We can determine the limitations on R, the resultant, by considering the extreme cases of the directions of the two forces.

Case 1: The two forces are in the same direction.
If the two forces are in the same direction, the resultant is the sum of the two forces, which is 2 N + 3 N = 5 N. Therefore, R ≤ 5 N.

Case 2: The two forces are in opposite directions.
If the two forces are in opposite directions, the resultant is the difference between the two forces, which is |2 N - 3 N| = 1 N. Therefore, R ≥ 1 N.

Therefore, the limitations on R are 1 N ≤ R ≤ 5 N. The correct answer is (d) 1 N ≤ R ≤ 5 N.
 
Because they provide the mechanical benefit of being able to apply modest forces over extended distances to move heavy loads, pulleys are utilized in a variety of mechanical systems. This is so that the pulley can raise things more successfully by rerouting the force that is applied to it. Despite the potential for friction and decreased efficiency, advantages frequently outweigh disadvantages.

Tip lang lods, google translate niyo sa Japanes, tapos ipadaan sa quillbot
Tapos pwed niyo translatre ulit sa iba iba, tapos quillbot ulit hehe
 
Last edited:
Because they provide the mechanical benefit of being able to apply modest forces over extended distances to move heavy loads, pulleys are utilized in a variety of mechanical systems. This is so that the pulley can raise things more successfully by rerouting the force that is applied to it. Despite the potential for friction and decreased efficiency, advantages frequently outweigh disadvantages.

Tip lang lods, google translate niyo sa Japanes, tapos ipadaan sa quillbot
Tapos pwed niyo translatre ulit sa iba iba, tapos quillbot ulit hehe
Ahh sige sige salamat po
 
Can you paraphrase this?
“The two forces lies in the quadrant 1 in the force table, so the resultant of can also be found in the quadrant 1. The equilibrant can be lovated in the opposite direction of the resultant which is in the quadrabt 3.”
 
In the force table, both forces are located in quadrant 1, so the resultant force can also be found in quadrant 1. The equilibrant force can be found in quadrant 3, which is the opposite direction of the resultant force.
 
To determine the force acting on each mass it was assumed that g = 9.80 m/s2. The value of g at the place where the experiment is performed may be slightly different from that value. State what effect (if any) it would have on the percentage error calculated for the comparisons. To test your answer to the question, leave g as a symbol in the calculation of the percentage error.
 


The percentage error for the comparisons would be affected if the value of g used in the calculation is different from the actual value of g at the place where the experiment is performed. The percentage error is calculated as the difference between the experimental and theoretical values, divided by the theoretical value, and multiplied by 100. If the value of g used in the calculation is not accurate, then the experimental values would be different from the actual values, and hence the percentage error would be affected.

To test this, let's consider an example:

Suppose the theoretical value of force is F = mg, where m = 2 kg and g = 9.80 m/s². The experimental value of g is measured to be g' = 9.83 m/s². The force is measured to be F' = 19.6 N.

The percentage error is given by:

% error = [(F' - F)/F] x 100

Substituting the values, we get:

% error = [(19.6 - 19.6)/19.6] x 100 = 0%

Now, if we leave g as a symbol in the calculation of the percentage error, we get:

% error = [(F' - F)/(mg)] x 100

Substituting the values, we get:

% error = [(19.6 - 19.6)/(2 x 9.80 x g)] x 100

Simplifying, we get:

% error = 0.51/g

So, we can see that the percentage error is inversely proportional to the value of g. Hence, if the actual value of g is slightly different from the value used in the calculation, the percentage error would be affected.
 

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