Chapter 29, Problem 60A

To determine

Whether lamp $L_1,L_2$ are lighted in the circuit:

Explanation of Solution

Introduction:

A reverse biased diode has p-side connected to the negative terminal of the battery and the n-side with the positive terminal of the battery. The flow of current is very limited. A forward biased diode has p-side connected to thepositive terminal of the battery and the n-side with the negative terminal of the battery. A large current flows across the diode.

The diode across $L_1$ is forward biased. Hence, current will flow through $L_1$ and it will glow. The diode across $L_2$ is reverse biased. Hence, a very small current will flow through $L_2$ and it will not be lighted.

Conclusion:

  $L_1$ is on and $L_2$ is off.