# Rise/Fall Time Sine Wave

Does anyone remember the formula for the rise/fall time for a sine wave...?

I thought I could calculate it but I did it wrong apparently
t1.
$$V_o sin(2*\pi*f*t)=.1 V_o$$

$$\frac{arcsin(.1)}{2 \pi f}$$

t2.
$$V_o sin(2*\pi*f*t)=.9 V_o$$

$$\frac{arcsin(.9)}{2 \pi f}$$

t2-t1...
but that isn't right

Last edited:

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Ahhh would I just have to change .1 and .9 to
.2 and .8

HallsofIvy
What, exactly, do you mean by "rise and fall time". The period of the sine function, sin(x), is $2\pi$- that's the "time" for an entire cycle. If, by "rise and fall" time, you mean the time for the function to go up to its highest value and then back to 0, that would be 1/2of that, $\pi$. Or, you might mean the time to rise and the time to fall. Each of those would be $\pi/2$.