Electric field energy and the capacitor
Answers are for parents and teachers.
1
A capacitor of 4 μF is charged to 50 V. What is its charge (μC)?
200
2
What is this capacitor’s energy (mJ)? (W = CU²/2)
5
3
The charge is 60 μC and the capacitance 3 μF. What is the voltage (V)?
20
4
If the voltage on a capacitor of fixed capacitance rises 3 times, by what factor does the energy rise?
9
5
How is a capacitor used in a camera flash?
It charges slowly and then releases its energy to the lamp almost instantly.