Question 3

1. Feb 4, 2005

kyang002

Question 4

What is the charge q_1?

What is the charge q_2?

What is the charge q_3?

Unsure of which equation to use, and the equations that I am looking at involve integration.

Φ = integral (E * dA) = EA sphere

Φ = q / ε

Can someone teach me how to do this problem?

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2. Feb 4, 2005

dextercioby

HINT:Use the property of the electric flux (which is a scalar) of adding wrt the same surface.You'll have to solve a very simple system of equations...

Daniel.

3. Feb 4, 2005

kyang002

Property of Electric Flux = EA cos theta? But there is no theta. Unsure of the area and of the E.

4. Feb 4, 2005

dextercioby

No.Let be $\Phi_{1}$ the electric flux generated by a charge $q_{1}$ through the (closed) surface S.Similar $\Phi_{2}$ for q_{2} [/itex].Then the total flux is simply the sum of Phi's which,due to the same denominator (epsilon),translates to the charges...

Daniel.

5. Feb 4, 2005

kyang002

So what is the charge of q_1, q_2, and q_3?

-q/E + (-2q/E) + 3q/E = 0/E = 0

The charge of each is 0?

6. Feb 4, 2005

dextercioby

No,you have to write equations of the type phi_{1}+phi_{2}=phi_{tot} for all 3 surfaces & will end up with an algebraic system of 3 eqn. with 3 unknowns,namely the charges.

Daniel.

7. Feb 4, 2005

kyang002

Okay, got it. The answers are 2q, q, -3q. Am I correct?