Question

if the total resistance of given circuit is 20 ohm ,then calculate the resistance of resistor X and current flowing through the circuit​

Answer 1

Answer:

Explanation:Given,

R1=10ohm

R2=X

R3=23ohm

R4=75ohm

V=6v

I= ?

R=20ohm

As R1 & R2 are connected in series

R'= R1+R2

R'=10+X ohm

Now R3 & R4 are connected in series

R"=R3+R4

R"=25+75

R"=100 ohm

Now,

1/R=1/R'+1/R"

1/20=1/10+X +1/100

=110+X/1000+100X

1000+100X=[110+X]20

1000+100X =2200+20X

100X-20X=2200-1000

80X=1200

X=120/8

X=15ohm

Now,

R= V/I

I=V/R

I=6/20

I=3/10

I=0.3A

Answer 2

The value of resistor x is 15 Ω and the current flowing through the circuit is 0.3 ampere.

Given,

The total resistance of the circuit = 20 Ω

To Find,

The value of resistor x.

Solution,

The 10 Ω resistor and x are connected in series.

So,

R' = (10+x) Ω

Same in the case of 25 Ω and 75 Ω

R'' = 25+75 = 100 Ω

Now the equivalent resistance of the circuit will be

1/R = 1/R'+1/R''

1/R = 1/(10+x) + 1/100

1/R = (100+10+x)/100*(10+x)

R = (1000+100x)/(110+x)

The value of R is gicen as 20 Ω

20 (110+x) = 1000+100x

2200+20x = 1000+100x

1200 = 80x

x = 1200/80 = 120/8 = 15 Ω

Now, the cureect flowing through the circuit will be

V = RI {0hm's law}

6 = 20*I

I = 6/20 = 0.3 ampere.

Hence, the value of resistor x is 15 Ω and the current flowing through the circuit is 0.3 ampere.