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blakableh
The angle between two pith balls if 40 degrees. Each pith ball has a mass of 0.3kg and the length of the string is 0.3m. Find the weight, electrostatic force between them, and the charge on each ball assuming the charges are equal.
Draw a free body diagram, representing all the forces on each ball. Forces on each ball :- 1) weight 2) elecrostatic force 3) tension force
sorry about the long wait
I found weight to be 1.9 N
but im having trouble finsing the electrostatic forces because i cannot find out what the radius is.
i think your question pertains to the equilibrium condition of the 2 masses if it is so then vertical component of the tension cancels out the weight. then electrostatic force = T cos 70 (if u take the line joining both of them as x axis and the perpendicular as y axis then the tension makes an angle of 70 degrees with the x axis) the radius is 0.6 cos 70 u will have only one unknown that is q and i already told u that Tsin 70 = mg best of luck !