Recent content by Aurelius120

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    Undergrad What causes knots and stress when untwisting ropes?

    Also since DNA is only made up to two strands, unlike ropes where each strand is made of smaller fibers(twisted in the same/opposite direction as the strands) Why will there be any supercoiling?
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    Undergrad What causes knots and stress when untwisting ropes?

    Is there a diagram or book or something that can show how the forces/stress balance everything and stay in place? Or get knotted when untwisted? (in a rope)
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    Undergrad What causes knots and stress when untwisting ropes?

    I don't know why I am coming back here now, after aeons. But can you explain it a bit simpler.
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    How does a transistor act as an amplifier?

    You mean this video? Here he says that if the collector circuit is open, all emitter current will flow through base and transistor will burn. But If there is no collector current, then why will there be any amplification, the only current should be the small base current which flows through...
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    How does a transistor act as an amplifier?

    So in this video he said that no matter how powerful a battery you apply across the N and N of the transistors, current will not flow unless a second battery is used across N and P because there is a depletion zone at one NP junction. But the P-region of NPN is very thin so can't the charge...
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    How does a transistor act as an amplifier?

    I was reading about transistors. There was one good video.. It said to treat the NPN transistor as two diodes. And so I did. I remember learning that a forward biased diode can be treated as a cell that causes a potential drop equal to the barrier potential (while a reverse biased diode is an...
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    Why is it necessary to start this experiment with the water level at 400mL?

    Oops. Yes this was my mistake. The second diagram I drew as the source of error like you were saying.
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    Why is it necessary to start this experiment with the water level at 400mL?

    Was he trying to say something different than the pictures I posted? I think I have made a mistake.
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    Why is it necessary to start this experiment with the water level at 400mL?

    What I meant is that I have to blow against atmospheric pressure but But here I have to blow against water pressure. I think I am making a mistake but I can't figure it. Sorry for the late reply.
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    Why is it necessary to start this experiment with the water level at 400mL?

    The Then as long as water level is at the level of upper rim of the bell or lower, we have to blow against atmospheric pressure since downwards pressure of water is zero. So the amount of exhaled air is same in 400mL or 0mL. Problem will be if water level is above bell at 0mL. Because of...
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    Why is it necessary to start this experiment with the water level at 400mL?

    Upthrust exerted by water on the bell (including the air trapped within,right) because that's the volume displaced.
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    Why is it necessary to start this experiment with the water level at 400mL?

    So if some air already exists for example at 400mL, it will be easier to blow into it (than doing so at 0mL) because there is more buoyancy?
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    Why is it necessary to start this experiment with the water level at 400mL?

    I meant this. (Water level at level of bell and bell resting on air pipe) Since normal reaction is balancing the bell. We have to blow against (weight-buoyancy), Right? Similar to if we had to lift/move a metal block with only force of exhaled air?
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    Why is it necessary to start this experiment with the water level at 400mL?

    So it will be like trying to blow away a chunk of solid metal? 😯😲
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    Why is it necessary to start this experiment with the water level at 400mL?

    But if it is at zero when the bell is resting at the water level,bell can't sink any further? Blowing air into it will still make it float, and give the required reading right?