# How to find magnitude of Q1 and Q2?

• s0mebody
In summary, two point charges, Q1 and Q2, are 6m apart. The electric field intensity at a point A, midway between the two charges, is 5 N/C directed toward Q2, and the potential at the same point is 45V. To find the magnitude of Q1 and Q2, we can use the equation VA = k [(Q1+Q2)/r] and the given information. We can also write an expression for the field using E = k(Q/r^2), giving us two equations and two unknowns to solve for Q1 and Q2.
s0mebody

## Homework Statement

Two point charges, Q1 and Q2 are 6m apart. The electric field intensity a point A, midway between the two charges is 5 N/C directed toward Q2, and the potential at the same point is 45V. Find:
a) the magnitude of Q1
b) the magnitude of Q2

## The Attempt at a Solution

This is what I got so far.
VA = k [(Q1+Q2)/r]
45 V = 9x109 [(Q1+Q2)/3]

Then I'm stuck at what to do next and what to do with E = 5 N/C

s0mebody said:

## Homework Statement

Two point charges, Q1 and Q2 are 6m apart. The electric field intensity a point A, midway between the two charges is 5 N/C directed toward Q2, and the potential at the same point is 45V. Find:
a) the magnitude of Q1
b) the magnitude of Q2

## The Attempt at a Solution

This is what I got so far.
VA = k [(Q1+Q2)/r]
45 V = 9x109 [(Q1+Q2)/3]

Then I'm stuck at what to do next and what to do with E = 5 N/C

5 N/C is the field intensity at the same point for which you've written an expression for the potential. You're also given the net field direction there. You'll want to write an expression for the field in terms of Q1, Q2, and their distances from that point. That will give you two equations and two unknowns...

## 1. What is the formula for calculating the magnitude of Q1 and Q2?

The formula for calculating the magnitude of Q1 and Q2 is given by the equation: Magnitude = Square root of (Q1^2 + Q2^2), where Q1 and Q2 are the magnitudes of the two charges.

## 2. How do I find the individual magnitudes of Q1 and Q2 if the total magnitude is known?

If you know the total magnitude of Q1 and Q2, you can use the Pythagorean theorem to find the individual magnitudes. Simply square the total magnitude and subtract the square of the other magnitude, then take the square root of the result. This will give you the magnitude of the remaining charge.

## 3. Can the magnitude of Q1 and Q2 be negative?

No, the magnitude of a charge cannot be negative. Magnitude refers to the absolute value or size of a quantity, so it is always a positive number.

## 4. How does the distance between Q1 and Q2 affect their magnitudes?

The magnitude of Q1 and Q2 is inversely proportional to the square of the distance between them. This means that as the distance between the two charges increases, their magnitudes decrease, and vice versa.

## 5. Is there a difference between the magnitude of a charge and its electric field?

Yes, there is a difference between the magnitude of a charge and its electric field. The magnitude of a charge refers to the amount of charge present on an object, while the electric field is a measure of the force exerted by that charge on other charges in its vicinity.

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