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A Wave Query watch

1. I have a question with a displacement-distance graph, and its asking me to give the points with maximum speed and the points where acceleration is minimum. Not sure how this works, any help appreciated...
2. Hi,

Max velocity is when the displacement from equilibrium is zero, and that is also when the acceleration is least, i.e. zero acceleration.

So to sum up, max velocity and min acceleration when zero displacement from equlibrium.

Hope that helps.
3. Thanks a lot, would you mind explaining it to me?
4. Consider a pendulum, it starts off at some displacement from the origin, it has a force pulling it torwards the centre that is proportional to the displacement, at that point it has maximum acceleration. All the while it moves towards the centre it is accelerating, until it reaches the centre, this is where acceleration stops, and eventually reverses, so it is at this stage that it has been accelerating continuously and hence has maximum speed. The whole process then goes in reverse with the pendulum accelerating in the opposite direction.

Do you know much calculus, because it is quite easy to understand if you consider the first and second derivatives of a sine curve.
5. Thank you, all has become clear.
Originally I had worked it out using the derivatives of the sine function, but I wasn't sure I was right because we haven't done it yet in Maths and I was doing it from what I've taught myself. Also, couldn't think of the words to go with the maths, but cheers!

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Updated: July 3, 2005
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