Question

a wire of length 1 m has a resistance of 2 ohm when connected to a cell the current in the wire is 3 ampere now at 2 metre length of the wire is connected to the same cell what is the resistance of the wire and current in it

Answer 1

hey mate !

Answers

For the 1m lamp:
Resistance= Resistivity × (Length ÷ Cross-sectional area)

that is, 2 ohm= resistivity × (1 ÷ Cross-sectional area)

Now, assuming that the wires are made of the same material and has the same cross-sectional area:

2 ohm ÷ 1 m = X ohm ÷ 2 m [here, X is the resistance of the second wire.

from here, the second wire's resistance comes as 4 ohms.

now, since the CELL is the SAME, the VOLTAGE will be the same.

we know, V=IR where V is the voltage, I is the current and R is the resistance.

Since the voltage remains constant,

3 amp × 2 ohm = I amp × 4 ohm [here, I amp is the current in the second wire]

From here, the current in the second wire comes as 1.5 amp.

I know it's pretty big a sum, but it helps going step-by-step. Hope this helped!

please mark it as brainliest.

Answer 2

Resistance = (Resistivity × Length)/ Area

2 = (Resistivity × 1)/ Area

Now assuming that it has same area

2 / 1 = x / 2

2 = x / 2

x = 4

V=IR

Both the voltage is same

IR = IR

3 × 2 = 4 × I

I = 1.5 A