Chapter 23, Problem 95A

(a)

To determine

To design: Circuit A requires that should one bulb burn out, all other bulbs continues to produce light.

Explanation of Solution

The effective resistance of the resistors when they are connected in series combination is as follows

  $R_s=R_1+R_2$  ......(1)

The effective resistance of the resistors when they are connected in parallel combination is as follows

  $\frac{1}{R_P}=\frac{1}{R_1}+\frac{1}{R_2}$  ......(2)

The following diagram which represents that one bulb burn out and all the other bulbs continues to produce light.

  

(b)

To determine

To design: Circuit B requires that should one bulb burn out, those bulbs that continue working must produce the correct intensity.

Explanation of Solution

The effective resistance of the resistors when they are connected in series combination is as follows

  $R_s=R_1+R_2$  ......(1)

The effective resistance of the resistors when they are connected in parallel combination is as follows

  $\frac{1}{R_P}=\frac{1}{R_1}+\frac{1}{R_2}$  ......(2)

The following diagram which represents that one bulb burn out that continues working must produce the correct intensity

  

(c)

To determine

To design: Circuit C requires that should one bulb burn out, one other bulb also will go out.

Explanation of Solution

The effective resistance of the resistors when they are connected in series combination is as follows

  $R_s=R_1+R_2$  ......(1)

The effective resistance of the resistors when they are connected in parallel combination is as follows

  $\frac{1}{R_P}=\frac{1}{R_1}+\frac{1}{R_2}$  ......(2)

The following diagram which represents that one bulb burn out and one other bulb will also go out.

  

(d)

To determine

To design: Circuit D requires that should one bulb burn out, either two other will go out or no other will go out.

Explanation of Solution

The effective resistance of the resistors when they are connected in series combination is as follows

  $R_s=R_1+R_2$  ......(1)

The effective resistance of the resistors when they are connected in parallel combination is as follows

  $\frac{1}{R_P}=\frac{1}{R_1}+\frac{1}{R_2}$  ......(2)

The following diagram which represents that one bulb burn out and either two other will go out or no other will go out