(adsbygoogle = window.adsbygoogle || []).push({}); 1st Problem

Two positive charges, each 4.18C, and a negative charge, -6.36C are fixed at the vertices of an equilateral triangle of side 0.13m.

Find the electrical force on the negative charge.

I don't know how to calculate electrical force on a specific charge :-S

and please explain why we take negative charge always as positive ?

please explain in detail why we take negative charge always as positive when applying coulomb's law.

2nd problem:

two charges q1 and q2, held a fixed distance d apart. (a) Find the strength of electric force that acts on qi. Assume that q1=q2=21.3C and distance=1.52m

(b)

A third charge q3=21.3C is brought in and placed as shown in figure, find the electric force on q1 now.

i've solved part (a) of the 2nd problem but i don't know how to solve the second part of it :-S

please explain

( I don't want the answers of these problems , i just need some help and explanation )

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# Coloumb's Law problem (calculating Electrical force on a charge)

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