An AM station is broadcasting a radio wave whose frequency is 1400 kHz.

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jandominic145
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Homework Statement


An AM station is broadcasting a radio wave whose frequency is 1400 kHz. The value of the capacitance in Figure 24.5 is 8.4 X10 -11 F. The Value of the capacitance in Figure 24.4 is 8.4X10-11 F. What must be the value of the inductance in order that this station can be tuned in the radio?


Homework Equations


c = f(wavelength)
S = cu

The Attempt at a Solution


but I'm not sure the fomula and i don't know how to get it
 
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Discussion

What is the natural frequency of an LC circuit oscillation?
 
f=1400 Khz
w= 2*pi*f

The natural frequency of an LC circuit is w=(L*C)^(1/2);
solving for L and plugging in the values L=1.5385*10^-10 Henries
 
There is a simple formula for use at radio frequencies, that uses realistic component values.

It is

L = 25330.3 / (F * F * C)

where L is in uH
C is in pF
F is in MHz

8.4 X10 -11 F is 84 pF
1400 KHz is 1.4 MHz
 
There is a simple formula for use at radio frequencies, that uses realistic component values.

It is

L = 25330.3 / (F * F * C)

where L is in uH
C is in pF
F is in MHz

8.4 X10 -11 F is 84 pF
1400 KHz is 1.4 MHz