Recent content by hmiamid

Hello PF, I just found a curious integral. I wondered if it comes from a bigger group of integral definitions: \int_0^\infty \mathrm{Si}(ax)e^{-x}\mathrm{d}x=\mathrm{atan}(a) Where Si(x) is the sine integral function \mathrm{Si}(x)=\int_0^x \frac{\mathrm{sin}x}{x}\mathrm{d}x I proved the...

Hello, and thanks for welcoming me in the forum of Physics Forums. I just found a curious integral that I solved by Taylor series. I wondered if it comes from a bigger group of integral definitions: ##\int_0^\infty \mathrm{Si}(ax)e^{-x}\mathrm{d}x=\mathrm{atan}(a)## Where Si(x) is the sine...

It's much clear now. I know why the ball hits harder the bottom, it's because of gravity :) Thanks for the information.

Hello, I would like to share a cool experiment... but not yet experimented for me. Suppose you have a ball of metal between two plates. The upper plate is charged - and the lower plate is charged + There is constant potential between the plates. When the ball touches the lower plate, it...