- #36
gracy
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As tension force never pushes it always pulls .So block should move forward.
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Calculating Tension in Friction & Pulley: Solving for a=3 m/s^2
In summary: No, there are three horizontal forces on the block. There is the force of gravity (mg), the force of the string connected to the block (T), and the force of the truck (a).You know which way the block will move relative to the car (since the string neither stretches nor breaks).I meant the force of the truck in forward motion.
- #37
gracy
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Is there any tension force in the end which is tied to wall (I have pointed out that end in my below diagram)
I think there should be.
I think there should be.
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In particular, forward relative to the car. So friction acts the other way, agreed? What, then, is the sum of forces?gracy said:
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Yes. What is the relationship between the tension there and the tension at the end attached to the block?gracy said:
- #40
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They should be same.As string and pulley is massless(assumption)
- #41
gracy
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Wait,I think I am getting the solution now.
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Right.gracy said:
- #43
gracy
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I wish Mass of flat car was given!
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As I posted previously, you don't care about the mass of the car or the forces on it because you know exactly how it is moving. Concentrate on the forces on the block and its acceleration.gracy said:
- #45
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Is it correct.
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Whether or not it is correct, it is irrelevant. Please just answer my questions in post ##34.gracy said:
- #47
gracy
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Backward.haruspex said:
No.haruspex said:
T-150N =30Kg multiplied by acceleration of the block.haruspex said:
Here I am struggling.haruspex said:
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Ok so far.gracy said:
The string is of constant length. If the car moves 1m, the top part of the string gets how much longer? What does that tell you about the length of the lower part? How far has the block moved?
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Yes.gracy said:
- #51
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I think the top part of the string should be
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That cannot be string, or the pulley would fall down. Must be a rod.gracy said:
The upper part of the string runs drom the wall to the pulley. How much longer does that get when the car advances 1m?
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gracy
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Same as distance covered by small block.haruspex said:
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No. Forget the block for the moment, and concentrate on the car, the pulley, the wall, and the length of string from wall to pulley. If the car moves 1m further from the pulley, how much longer is that part of the string?gracy said:
- #55
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Total length of string - length of the top part of the string ?haruspex said:
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No, I'm asking about that top part of the string, the part that runs horizontally from the wall to the pulley.gracy said:
- #57
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gracy said:Total length of string -(minus) length of the top part of the string .Right?/QUOTE]
- #58
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Thank you for your patience .
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If the car moves 1m further from the wall, how much further is the pulley from the wall? So how much longer is the piece of string from the wall to the pulley?
- #60
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1 meter?
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Right. So what would be the change in length of the lower part of the string, the part that runs from the block to the pulley?gracy said:
- #62
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1 meter .haruspex said:
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Longer or shorter?gracy said:
- #64
gracy
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Shorter?haruspex said:
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Right. So how much closer is the block to the pulley?gracy said:
- #66
gracy
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1 meter.so distance covered by block is 1 meter,right?haruspex said:
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It is one metre closer to the pulley. But the pulley has moved how far?gracy said:
- #68
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1 meter?haruspex said:
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Right. So the pulley is one metre further from the wall, and the block is one metre closer to the pulley. So how far has the block moved away from the wall?gracy said:
- #70
gracy
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1 meter.haruspex said: