Question 10: NCERT Solutions for 12th Class Physics: Chapter 7-Alternating Current
A radio can tune over the frequency range of a portion of MW broadcast band: (800 kHz to 1200 kHz), if its LC circuit has an effective inductance of 200 μH, what must be the range of its variable capacitor?
For tuning, the natural frequency i.e., the frequency of L-C oscillations should be equal to frequency of radio waves received by the antenna in the form of same frequency current in the L-C circuit. For tuning at 800 kHz, required capacitance
So, the variable capacitor should have a frequency range between 87.9 pF to 197.8 pF.
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NCERT Solutions for 12th Class Physics: Chapter 7-Alternating Current