What is (a) the highest, (b) the lowest total resistance that can be secured by combinations of four coils of resistance 4 Ω, 8 Ω, 12 Ω, 24 Ω?

Asked by Vishal kumar | 1 year ago |  199

##### Solution :-

(a) If the four resistors are connected in series, their total resistance will be the sum of their individual resistances, and it will be the highest. The total equivalent resistance of the resistors connected in series will be 4 Ω + 8 Ω + 12 Ω + 24 Ω = 48 Ω.

(b) If the resistors are connected in parallel, then their equivalent resistances will be the lowest. Their equivalent resistance connected in parallel is

$$R = \frac{1}{\frac{1+1+1+1}{4+8+12+24}}=\frac{24}{12}=2\,\Omega$$

Hence, the lowest total resistance is 2 Ω

Answered by Shivani Kumari | 1 year ago

### Related Questions

#### Explain the following. a. Why is the tungsten used almost exclusively for filament of electric lamps?

Explain the following.

a. Why is the tungsten used almost exclusively for filament of electric lamps?

b. Why are the conductors of electric heating devices, such as bread-toasters and electric irons, made of an alloy rather than a pure metal?

c. Why is the series arrangement not used for domestic circuits?

d. How does the resistance of a wire vary with its area of cross-section?

e. Why copper and aluminum wires are usually employed for electricity transmission?

#### An electric heater of resistance 8 Ω draws 15 A from the service mains 2 hours. Calculate the rate at which heat is developed in the heater

An electric heater of resistance 8 Ω draws 15 A from the service mains 2 hours. Calculate the rate at which heat is developed in the heater.

#### Which uses more energy, a 250 W TV set in 1 hr, or a 1200 W toaster in 10 minutes?

Which uses more energy, a 250 W TV set in 1 hr, or a 1200 W toaster in 10 minutes?

#### Two lamps, one rated 100 W at 220 V, and the other 60 W at 220 V, are connected

Two lamps, one rated 100 W at 220 V, and the other 60 W at 220 V, are connected in parallel to the electric mains supply. What current is drawn from the line if the supply voltage is 220 V?