Electric Charge Physics Example 2

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Example 2

medium
Two charged spheres carry charges of +5 μC+5 \text{ } \mu\text{C} and −3 μC-3 \text{ } \mu\text{C}. They are brought into contact and then separated. What is the charge on each sphere afterward?

Solution

  1. 1
    Total charge is conserved: Qtotal=+5+(−3)=+2 μCQ_{\text{total}} = +5 + (-3) = +2 \text{ } \mu\text{C}.
  2. 2
    When identical conducting spheres touch, charge distributes equally.
  3. 3
    Each sphere gets: Qeach=Qtotal2=+22=+1 μCQ_{\text{each}} = \frac{Q_{\text{total}}}{2} = \frac{+2}{2} = +1 \text{ } \mu\text{C}

Answer

Qeach=+1 μCQ_{\text{each}} = +1 \text{ } \mu\text{C}
Electric charge is conserved — it cannot be created or destroyed, only transferred. When conductors touch, charges redistribute until equilibrium is reached. For identical spheres, charge splits equally.

About Electric Charge

A fundamental property of matter that causes it to experience a force in an electromagnetic field. Measured in coulombs (C).

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