Question

A variable capacitor is used to tune a radio to the desired station. At the low end of the AM band​ (550kHz), will the capacitive reactance ​(XC​) be higher or lower than it is at the high end of the band​ (1440kHz)?

Answer 1

The capacitive reactance (XC) will be higher at the low end of the AM band as compared to the high end.

Step-by-step explanation:

In an RLC circuit used to tune a radio, a variable capacitor is connected to a fixed inductor. At the low end of the AM radio band (550kHz), the frequency is lower compared to the high end (1440kHz). At lower frequencies, the capacitive reactance (XC) of a capacitor is higher than at higher frequencies.

Therefore, at the low end of the AM band, the capacitive reactance will be higher than it is at the high end of the band.