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Thank you We sneak and here's yours from obtuse your

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brought to you by waves We tried to go surfing

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ones but apparently it's not cool for surfers toe wear

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water wings All right check out the following diagram Given

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the plot for velocity above which of the following plots

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marks displacement and which marks acceleration here your potential answers

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It will answer this question There are a few important

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things to remember First thing to remember is that calculus

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is fun Just keep repeating that to yourself over and

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over until you really start to believe it We also

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need to remember that velocity is the slope of the

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plot for displacement versus time and acceleration is the slope

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of the plot for velocity versus time Oh we almost

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forgot the third thing to remember when plotting the slopes

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of waves like this is that the slope of a

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sine wave is a co sign way So in the

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slope of a co sign wave is an inverse sine

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wave a negative sign Wake now that we've got all

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this down let's just take a look at our first

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plot This first part sure looks like a co sign

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Wave tow us So if this is the plot for

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velocity and velocity is the slope for displacement versus time

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than the plot for disco placement will be a sine

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wave if we look at our three choices will see

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that plot is a co sign Wave b is a

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negative sign wave and see is a sine wave also

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looking at our original plot for velocity the second part

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of it the flat line is a constant negative value

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right Well after all the whole thing is below zero

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on the y axis So philosophy is a constant negative

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value in this plot the displacement plot has to include

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a segment with a constant negative slope and plot c

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is the only one that fits the bill Now remember

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what we said earlier Acceleration is the slope for velocity

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If velocity kicks off with a cho sun wei acceleration

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starts with a negative sign and just to be clear

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that's s i n e s i g and also

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the slope of a flat line is zero So the

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acceleration plot should also be zero for the second segment

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Looking over our plot options we only have one negative

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Sine wave and only one with a segment that has

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a flat line of zero Lucky for us they're both

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part of a plot B If we take all that

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we just did Well we'll see The correct answer is

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option d plot See mark's displacement while plot b marks

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acceleration that was a hard one Clearly waves and physics

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can be tricky very very tricky but they're usually safer 00:02:24.17 --> [endTime] than waves in the ocean Please

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