What is the total capacitance of two capacitors in parallel if the first is 15MFD at 370VAC and the second is 20MFD at 440VAC?

To calculate the total capacitance of two capacitors connected in parallel, you simply add their capacitances together. In this case, the first capacitor has a capacitance of 15 microfarads (MFD) and the second capacitor has a capacitance of 20 MFD.

The formula to find the total capacitance ( C_{total} ) in parallel is:

[ C_{total} = C_1 + C_2 ]

Applying this to the given values:

[ C_{total} = 15 MFD + 20 MFD = 35 MFD ]

When capacitors are connected in parallel, the voltage ratings (370 VAC for the first and 440 VAC for the second) do not change the total capacitance; however, it is common to consider the lower voltage rating when determining the operating voltage of the combined capacitors. In this situation, while the total capacitance is 35MFD, the lower voltage of 370VAC is needed for safety.

Therefore, the total capacitance of the two capacitors in parallel is correctly given as 35MFD@370VAC. This reasoning supports the answer that the total capacitance amounts to 35MFD when the first and second capac