Answers
Answer:
1.26 amp or 1.2 A (b)
Explanation:
According to the given question,
3 and 0.5 ohm resistors are in series whereas 10 and 15 ohm resistors are in parallel to each other.
Voltage = 20 V
And we are asked to find current through 10 ohm resistor.
So, we know for series combination,
- R = R1+R2
R1 and R2 are in series combination.
And again, for parallel combination,
- 1/R = 1/R1 + 1/R2
R1 and R2 are in parallel combination.
Where R is equivalent resistance in both case.
- So, R = 3+0.5 = 3.5 Ohm
(As they are in series)
Where R is equivalent resistance of series combination.
- 1/R' = 1/10 + 1/15
(As they are in parallel)
Where R' is equivalent resistance of parallel combination.
- R' = 10×15/25
- R' = 6 ohm
Now, these 6 ohm and 3.5 ohm are in again series combination.
Hence, Req = 6+3.5 = 9.5 ohm
So, Current in the circuit will be according to ohm law,
- V= IR
- I = V/R
- I = 20/9.5
- I= 2.10 amp ( approx )
Now current through 10 ohm will be known by potential difference between 10 ohm.
So, Potential drop by 3.5 resistance
- V = 2.10 × 3.5
- V = 7.36 V
Hence, Potential difference between the 10 ohm resistor is, 20-7.36 = 12.64 V
Alternatively,
- V = IR
- V = 2.10× 6
- V = 12.6 V
So, Current in the 10 ohm resistance is;
- V = IR
- I = V/R
- I = 12.6/10
- I = 1.26 Amp ans.