We had this at our physics class, but since my concern only involves computation, I posted it here. I admit I was not paying attention and was just jotting down what my teacher was scribbling on the board. These are the equations in the exact order she wrote it:(adsbygoogle = window.adsbygoogle || []).push({});

[tex]k(e) = \frac{mv^2}{2}[/tex] [Eq.1]

[tex]v = \frac{2 k(e)}{m}[/tex] [Eq.2]

[tex]\frac{mv^2}{m} = \frac{2 k(e)}{m}[/tex] [Eq.3]

[tex]v^2 = \frac{2 k(e)^2}{m^2}[/tex] [Eq.4]

I.. quite.. do not follow the significance of Eq.2. And I'm not sure my teacher wrote Eq.4 correctly, because I would simply get [tex]v^2[/tex] from Eq.1 like this:

[tex]k(e) = \frac{mv^2}{2}[/tex] [Eq.1]

[tex]2k(e) = mv^2[/tex]

[tex]v^2 = \frac{2 k(e)}{m}[/tex]

So, I'm hoping someone could explain whether Eq.2 is really a derived equation.. and if it is, to be patient enough to explain how my teacher got from Eq.1 to Eq.4. I don't really know what's going on, and she's requiring us to solve the equation

[tex]F(e) = \frac{kq_1q_2}{r^2}[/tex]

and I don't know what she is really looking for. Thanks in advance!

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# Homework Help: Is this a problem of derived equation?

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