Question

A resistor with R = 850 Ω is connected to the plates of a charged capacitor with capacitance C= 4.62 μF Just before the connection is made, the charge on the capacitor is 6.90 mC. (a) What is the energy initially stored in the capacitor?

Answer 1

To find the energy initially stored in the capacitor, calculate the potential difference with the given charge and capacitance, and then use that to determine the energy using the formula (1/2)QV.

Step-by-step explanation:

To calculate the energy initially stored in the capacitor, we can use the following formula: U = (1/2)QV, where U is the energy, Q is the charge and V is the potential difference across the capacitor. However, we are not given V directly in this case, but we can find it since we have the charge Q and the capacitance C. The potential difference can be found by rearranging the relation Q = CV to V = Q/C.

First, calculate the potential difference: V = 6.90 mC / 4.62 μF. Convert mC to coulombs and μF to farads yielding V = 6.90 x 10-3 C / 4.62 x 10-6 F.

Then calculate the energy stored using this potential difference: U = (1/2) * (6.90 x 10-3 C) * V. After plugging in the value for V that you calculated, you can find the energy stored in joules (J).