Three equal charges, 2.0 × 10–6 C each, are held fixed at the three corners of an equilateral triangle of side 5 cm. Find the Coulomb force experienced by one of the charges due to the rest two.
Given:
Let the force due to charge at corner B, C be FB, FC.
Charge at each corner,
.
Note that the length of side of the triangle is
.
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Formula used:
By Coulomb’s law, the electric force is given by:
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Where ϵ0 is the permittivity of free space
k is the electrostatic constant
q1 and q2 are the magnitude of charges
r is the distance of separation between the charges
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Putting the values in the above formula, we get
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We can see from the diagram that FCand FBcab be resolved into theirs x and y components.
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The y’s are in the same direction and add up but the x’s are in the opposite direction, hence they cancel out.
Hence,
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