# Calculating the Electric Field Strength at a certain point with multiple point charge

## Homework Statement

Attached picture with the given variables and questions stated.

E = kq / (r^2)

## The Attempt at a Solution

I've taken found the linear electric field magnitudes in relationship to the point

q1 = 3.37e-9
q2 = 6.74e-9
q3 = 3.92e-9

r1 = .647m
r2 = 1.941m

E1 = (k*(q1))/(r1) = 72.3540189055
E2 = (k*(q2))/(r2) = 16.0789708679

I am having difficulty figuring out how to calculate the third vector into the total, any thoughts?

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SammyS
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## Homework Statement

Attached picture with the given variables and questions stated.

E = kq / (r^2)

## The Attempt at a Solution

I've taken found the linear electric field magnitudes in relationship to the point

q1 = 3.37e-9
q2 = 6.74e-9
q3 = 3.92e-9

r1 = .647m
r2 = 1.941m

E1 = (k*(q1))/(r1) = 72.3540189055
E2 = (k*(q2))/(r2) = 16.0789708679

I am having difficulty figuring out how to calculate the third vector into the total, any thoughts?
Hi fisixC.

Pythagoras tells us that:
r32 = r12 + r22

The y-component of r3 is |r1|/|r3| .

The x-component of r3 is ‒|r2|/|r3| .

It may also help to notice that 1.941 = 3×0.647 .

Therefore,

|r1|/|r3| = |r1|/√(10)

|r2|/|r3| = 3|r1|/√(10)