Question

Question 8 1 pts In the circuit shown, L1 = 20 uH, Ls = M= 15 uH, and Rs = 1 12. The load resistor has R= 2500 2. Vs R What percentage of forward current returns in the shield of the coax at 80 kHz? less than 5% between 5% and 50% between 50% and 95% more than 95%

Answer 1

As the characteristic impedance of an coaxial cable is about 50ohms( i.e Zc=50ohms) which is very much less as compare to load resistance( R=2500ohms).

Now, the reflection coefficient of current is given by,

$\frac{Z_{c}-R}{Z_{c}+R}$

=$\frac{50-2500}{50+2500}$

= -96%(approx) {Here negative sign shows that the forward current is getting reflected}.

So, the correct option is d.