Pulley and Blocks: Is My Answer Correct?

hquang001 · 2021-02-27T20:39:11+00:00

1 Block m2: m2g - 2T = m2a2 (1) Block m1: ∑F= ma T= m1a1 = m1.2a2 (2) Cancel T in (1) and (2) I have : m2g = a2 (4m1 + m2) => a2 = m2g / (4m1 + m2) => a1 = 2m2g / (4m1 + m2) Is my answer correct ? Thank you

Thread starter hquang001
Start date Feb 27, 2021
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Blocks Pulley

In summary, pulleys and blocks work together to create a mechanical advantage, making it easier to lift a heavy load with a smaller force. A fixed pulley changes the direction of the force while a movable pulley reduces the amount of force needed. The mechanical advantage of a pulley system can be calculated by dividing the load weight by the effort force, and can be increased by adding more pulleys. Real-world applications of pulleys and blocks can be found in various industries and everyday objects.

Feb 27, 2021

hquang001

Homework Statement: In term of m1, m2 and g, find the acceleration of each block. There is no friction anywhere in the system

Relevant Equations: ∑F= ma

Block m2:
m2g - 2T = m2a2 (1)
Block m1:
∑F= ma
T= m1a1 = m1.2a2 (2)

Cancel T in (1) and (2) I have :
m2g = a2 (4m1 + m2) => a2 = m2g / (4m1 + m2)

=> a1 = 2m2g / (4m1 + m2)

Is my answer correct ? Thank you

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Feb 27, 2021

TSny

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Your work looks correct to me.

Feb 27, 2021

hquang001

TSny said:

Your work looks correct to me.

Thank you

1. How do pulleys and blocks work together?

Pulleys and blocks work together to reduce the amount of force needed to lift an object. By using multiple pulleys and blocks, the weight of the object is distributed among the ropes, making it easier to lift.

2. What is the mechanical advantage of using pulleys and blocks?

The mechanical advantage of pulleys and blocks is the ratio between the weight of the object being lifted and the force needed to lift it. The more pulleys and blocks used, the greater the mechanical advantage and the easier it is to lift the object.

3. How many pulleys and blocks do I need to lift a certain weight?

The number of pulleys and blocks needed depends on the weight of the object and the desired mechanical advantage. Generally, the more pulleys and blocks used, the easier it will be to lift the object. However, too many pulleys and blocks can also create friction and decrease the efficiency of the system.

4. Can I use pulleys and blocks to lift objects vertically?

Yes, pulleys and blocks can be used to lift objects vertically. In fact, this is the most common way they are used. By attaching one end of the rope to a fixed point and pulling on the other end, the object can be lifted vertically.

5. Can I use pulleys and blocks to lift heavy objects by myself?

Yes, pulleys and blocks can make it possible for one person to lift heavy objects that would otherwise be impossible to lift alone. By using multiple pulleys and blocks, the weight of the object is distributed, making it easier for one person to lift.