Final answer:
The electric energy stored in a 20nF capacitor charged by a 90.6 V battery is calculated using the formula for energy stored in a capacitor, yielding an energy of 8.2 × 10^-8 J (3 significant figures).
Step-by-step explanation:
The question is about calculating the electric energy stored in a capacitor when it is charged by a battery. To find the energy stored in a 20nF (nanoFarads) capacitor charged to 90.6 V, we can use the formula:
Ecap = ½ × C × V^2
where C is the capacitance and V is the voltage. Plugging in the values:
Ecap = 0.5 × 20 × 10^-9 F × (90.6 V)^2
After carrying out the calculations, we get:
Ecap ≈ 0.082 µJ
this value would be expressed in exponential format as 8.2 × 10^-8 J, using three significant figures (3 SF).