Recent content by DanielGuh

This video helps a lot, thanks!

Ohh I got it, the unit should be change, and when I use sin I find the answer is 4.51m. However, I don't know why do we use sin instead of cos.

Fg = Fc Fg = 2.3g*9.8m/s^2*cos(28)=19.90N 19.90 = (8.99*10^9)*(4*10^-6)*(6*10^-6)/(r^2) 1/(r^2) = 92.23 r = 0.104m However, it's not one of the option...