Question

plzz give the procedure to solve this...plzz..​

Answer 1

Answer:

Explanation:

answer 1 :-

voltage , and current is given , resistance remain constant so,

using R = V/I

R = 20/ 3 ohm

now use this in second part so,

I = 30 / 20 /3

I = 30*3/20

I = 90 / 20

I = 4.5 ampere

answer 2:-

using the resistivity formula

R = б*L / A

R = 1.7 * 10 ^-8 * 1 m / 0.002 m

Resistance = 8.5 * 10^-3 ohm

answer 3 :-

first assume it has 3 resistors

first they were in series so,

total resistance = R 1 + R 2 + R 3

Now they are in parallel

1 / R = 1 / R 1 + 1 / R 2 + 1 / R 3

Now simplify,

answer 4:-

(a)  

In this we are going to keep

6 ohm and 12 ohm resistors parallel

and the 4 ohm in series

first calculate the parallel resistance and than add the 4 ohm

first case:-

1 / 6 + 1 / 12

= 2 + 1 / 12

= 4 ohm

now add

4 + 4  = 8 ohm

(b)

we know that

when we keep resistors in series resistance increases , and when we keep them parallel resistance decreases

FOR HIGHEST RESISTANCE ( series)

4 + 6 + 12 = 22 ohm

FOR LOWEST RESISTANCE ( parallel)

1 / 4 + 1 / 6 + 1 / 12

= 3 + 2 + 1 / 12

= 6 / 12

= 2 ohm

I HOPE THIS HELPS YOU

ALL THE BEST