Question

please solve the question in the image
Topic : current electricity​

Answer 1

Answer:

First 16 and 24 in series that'll be 40

Then 40 in parallel with 80 that'll be 80*40/80+40 = 80*40/120 = 80/3

Then,

80/3 = 26.67 in series with 26

will be 52.67

Lets take 53 as 50 for easier calculation cause next 53 is going to be in parallel with 200 so it wouldn't affect much

50 in parallel with 200 will be (200)*50/200+50 = 200*50/250 = 200/5 = 40

Then, finally 40 in series with 20 will be 60 ohms and hence the current drawn from the battery will be

6/60 = 0.1 Amp by Ohm's Law.

Next to find out the potential difference across the 200 ohm resistor.

We saw how the system to the right of 200 ohms which includes 26 ohm, 80 ohm,16 and 24 ohm was turning out to give us an overall effective resistance of 52.67 which can be approximated to be 50 ohms.

So, while the current has passed through the initial 20 ohms, it will have to branch out at the junction of which one of the branches is 200 ohm resistor and the other branch is the system which has the effective resistance of 52.67 or approx 50 ohms.

So, by the relationship that current and resistance are inversely proportional that is more the resistance less the current and vice versa

we can write the current in 200 ohm branch will be 50/200+50*total current= 1/5*total current = 1/5*(0.1) = 0.02 Amp = 20 mA

Potential difference across the 200 ohm resistor will be = 200*0.02 = 4 Volts

An even easier approach would have been to observe the potential drop across the first 20 ohm resistor that'd be 20*0.1 = 2 volts, so what remains is 4 volts out of the 6 volts that the battery has to offer and next the 200 ohm resistor is going to be in parallel with the other remaining system which means yeah the answer should be 4 volts by this method too.

Hope this helps you! :)