- #36

paulo84

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A string transports a wave. It can act as a medium.

Thank you, I'm already more clear.

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- Thread starter paulo84
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- #36

paulo84

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A string transports a wave. It can act as a medium.

Thank you, I'm already more clear.

- #37

paulo84

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- #38

Dale

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What is a beta wave?is there a part in physics which deals with strings carrying beta waves?

- #39

paulo84

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I would start here:

https://en.m.wikipedia.org/wiki/String_(physics)

https://en.m.wikipedia.org/wiki/Wave

Thanks. Relative to the 'strings' article - I think I should revisit my textbook first! It's of course far beyond my current learning, I'm just hoping to get a somewhat correct understanding of more complex ideas.

- #40

paulo84

- 112

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What is a beta wave?

Sorry I meant beta ray. I could have sworn they were called 'beta waves' in school. Woops.

- #41

paulo84

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I withdraw my last question.

- #42

paulo84

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I'm starting to think Sophie is right.

- #43

Dale

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Yes, @sophiecentaur usually is right!I'm starting to think Sophie is right.

- #44

paulo84

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Yes, @sophiecentaur usually is right!

That somehow doesn't surprise me. :) One final thought (for now) - lekh2003's answer gave me a very basic understanding of one aspect of string theory. A wikipedia article would have been far, far harder to decipher.

- #45

Mark44

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It has already been discussed, but IMO bears repeating. Time is NOT change of displacement. If s represents the displacement of some object, then a change in displacement is usually represented as ##\Delta s##. Velocity is the instantaneous rate of change of displacement, and can be written either as s' or s'(t) or ##\frac {ds}{dt}##. This last notation is the derivative of s with respect to t. "Change of change of <whatever>" is not good terminology. We always talk about the "rate of change" of some variable with respect to some other variable. In this context, the "other variable" is time.OK, so time is change of displacement. Speed is change of change of displacement.

Without getting too deep into the weeds of calculus (which is what we're really talking about when we are discussing derivatives), ##\frac {ds}{dt}## is defined in terms of a limit. IOW, ##\frac{ds}{dt} = \lim_{\Delta t \to 0}\frac{\Delta s}{\Delta t} = \lim_{h \to 0}\frac{s(t_0 + h) - s(t_0)}{h}##. Suffice it to say, that we can approximate the velocity by taking smaller and smaller time increments in doing the calculation.

Speed and velocity are different. Velocity is usually taken as a vector quantity, as it indicates a rate of motion in some direction. Speed, on the other hand, is a scalar quantity, with speed = |velocity|. A car's speedometer records the magnitude of the car's velocity, but doesn't indicate the direction.

No, accleleration the rate of change of the velocity with respect to time. Again, if s is displacement, then s'(t) is velocity, and s''(t) or ##\frac {d^2s}{dt^2}##, also a vector quantity, as direction is significant.Acceleration is change of change of change of displacement (or of distance, sorry I'm not sure whether acceleration is a vector or a scalar).

No. Dimension has nothing to do with any of this.It seems to me, with each new layer of change you're adding a new dimension.

Yes.Therefore there must be an infinite number of dimensions of space. Or am I getting space mixed up with motion?

- #46

paulo84

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- #47

paulo84

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- #48

jbriggs444

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Duration is what clocks measure, distance is what rulers measure. Clocks and rulers are different. If you are getting so far out in the weeds that the distinction escapes you, it's time to come back to the house.

- #49

paulo84

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Duration is what clocks measure, distance is what rulers measure. Clocks and rulers are different. If you are getting so far out in the weeds that the distinction escapes you, it's time to come back to the house.

Thanks, I am able to distinguish between space and time for the practical purposes of everyday living. I stand by my point.

- #50

Dale

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This is logically inconsistent. If they were the same thing then you could not distinguish between them.I am able to distinguish between space and time for the practical purposes of everyday living. I stand by my point.

- #51

paulo84

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Which one of us is making a circular argument?

- #52

Dale

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Neither of us.

- #53

paulo84

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OK. So should I give up?

- #54

paulo84

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- #55

Dale

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I think it is time to close this thread. If you wish to learn physics then please open a new thread with a substantive question

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