What is the time needed for A to move 50cm downward?

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To determine the time needed for object A to move 50 cm downward with an added weight, the discussion highlights the use of free body force diagrams and the application of constant acceleration formulas. After the first 50 cm, when the weight is removed, A continues to move but does not accelerate further due to the absence of a net external force, in accordance with Newton's First Law. The velocity at the end of the first 50 cm remains constant for the subsequent movement. The time for the second 50 cm is calculated based on this constant velocity, leading to the conclusion that A will take the same time to move the next 50 cm as it did for the first segment. The final answer for the time taken is suggested to be around 5 seconds.
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Both mass of A and B is 0.49kg. A ring of 0.001kg is added on A to let A begin to move downward.
(a) what is the time needed for A to move 50cm downward?
(b)What is the time needed for A to move another 50cm downward if the ring was taken off imediately after first 50cm?


I can find the the answer of (a) but i don't know how to solve the 2nd question since I have no idea at all about how to find out the acceleration after first 50cm. Can anyone help me?
 

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I assume you did some free body force diagrams and analysed them for the first part?
A had the extra weight and so due to f=ma began to move.
I assume you then used constant acceleration formulae to calculate the time it took for A to move 50cm.

Now...

After the first 50cm, the weight is removed. What does this mean in terms of the equating of forces?... Does A still accelerate? Does it stop dead? Does it keep the same velocity?
Think about Newton's First Law : An object will remain at rest or at constant velocity unless acted upon by an external force.
 
A is still moving ...is it still accelerate with the same acceleration as previous?
How does Newton`s First Law relate with this question?
 
frozen7 said:
A is still moving ...is it still accelerate with the same acceleration as previous?
How does Newton`s First Law relate with this question?
"An object will remain at rest or at constant velocity unless acted upon by an external force."

After the additional weight is removed, there is no (net) external force- A will continue to move with no acceleration but at the speed it had at 50 cm.
 
Thanks. Is the answer equal to 5s?
Assume s=0.5
u= the speed at first 50cm
a=0
 
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