A student has a resistance wire of 1 ohm.If the length of this wire is 50cm,to what length he should stretch it uniformly so as to obtain a wire of 4 ohm resistance?

Question

Answer

Calculating the New Length of Resistance Wire

Resistance of a wire is directly proportional to the length of the wire. So, to obtain a resistance of 4 ohms, we need to increase the length of the wire proportionally. Here's how:

Using Ohm's Law

We can use Ohm's law, which states that resistance (R) is equal to voltage (V) divided by current (I).

R = V/I

Calculating the Current

Now, we know that the resistance of the wire is 1 ohm. Let's assume that the current passing through the wire is 1A. Therefore, the voltage across the wire would be:

V = IR

V = (1A) x (1 ohm)

V = 1V

Calculating the New Length

Now, we want to find out the new length of the wire that would provide a resistance of 4 ohms. We can use the formula:

R = (ρ x L) / A

Where:

R = Resistance

ρ = Resistivity of the wire material

L = Length of the wire

A = Cross-sectional area of the wire

Since the wire material is not mentioned, we assume that the resistivity of the wire material is constant. Therefore, we can say that:

R1 / L1 = R2 / L2

Where:

R1 = Initial Resistance of the wire

L1 = Initial Length of the wire

R2 = Final Resistance of the wire

L2 = Final Length of the wire

Plugging in the values:

1 ohm / 0.5m = 4 ohms / L2

L2 = 2 meters

The Final Answer

Therefore, the student should stretch the wire uniformly to a length of 2 meters to obtain a wire of 4 ohm resistance.

Answer

No one knows the solution of this problem?pls tell me fast...I have tried so much but unable to solve this...

Answer

He should stretch the wire up to 200 cm for getting 4 ohm resistanceAs, R = p*I/ATherefore, 1=p*50/AR=>p/A=1/50---(1)Now resistance =4 ohmR=p*I/A4=p*I/AFrom (1)p/A=1/50=> 4=(1/50)I=> I = 200cm

Answer

Resistance is directly proportional to length. so, if resistance is 4times then L. also become 4times

Answer

I Think he has to stretched it 200 cm

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