A web page designer creates an animation in which a dot on a computer screen has a position of [tex]r^\rightarrow [4.40cm + (2.20cm/s^2)t^2]\underlinei + (5.00 cm/s)t\underlinej[/tex](adsbygoogle = window.adsbygoogle || []).push({});

okay i already have the correct answer, but i would like to know how the author got it. i came close to getting the correct answer.

Question.) Find the instantaneous velocity at t=1.0. Give your answer as a pair of components separated by a comma(x,y).

ok to find the instantaneous velocity, i need to find the derivative of the function...

d/dt r = 2(2.20cm/s)*2(t)i + (5.00cm/s)

plug in 1.0 for t and got....

(8.8cm/s,5.00cm/s) <--- my answer

(4.40cm/s, 5.00 cm/s) <--- correct answer

it looks like the correct answer divided my x-component by 2, but why? can someone explain?

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# Homework Help: Instantaneous velocity animation

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