Question

6) Repeat experiment 5) a) but now use the stored energy meter. Why do you think the change takes place. charge remains constant across the plates but voltage will increase as separation increases. As voltage increases, stored energy increases. Where does this energy come from / go to?

Answer 1

Answer:

the energy comes from the increase in the electric field

Explanation:

The capacitance is

      C = ε₀ A / d

The electric charge on the condenser plates

    Q = C ΔV

     

The stored electrical energy is

       U = ½ C ΔV²

       ΔV = E d

     U = ½ (ε₀ A / d) (E d)²

    U = ½ ε₀ A d E²

We see that the stored energy is proportional to the square of the electric field, so the capacitor can increase its energy with increasing voltage

In short, the energy comes from the increase in the electric field