a 4 ohm resistance wire is doubled on it calculate the new resistance of the wire

Dear Student,

In this query we consider wire double on it means to fold the length of wire. It means its length will get half and area of cross section will get double.

Let the resistance of the wire originally 'R' of length 'l' and area of cross-section 'A' with resistivity of material is 'ρ', Then

Now, for new arrangement,

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- 131

We know

P= RA/l

Now, initially we have -

R= 4 ohm

Area = A

Length = l

So,

P=4A /l -----------(1)

Now when wire get doubled then -

Length get half i.e l/2

Area of Cross - section get doubled i.e 2A

Resistance becomes R'

So,

P=R'2A/l/2

= 4R'A /l ---------- (2)

Now we know that resistivity of a wire never get affected by change in shape and size. So,

Eqn- (1) = Eqn- (2)

4A/l = 4 R'A/l

1 = R'

Hence new resistance is 1 ohm

P= RA/l

Now, initially we have -

R= 4 ohm

Area = A

Length = l

So,

P=4A /l -----------(1)

Now when wire get doubled then -

Length get half i.e l/2

Area of Cross - section get doubled i.e 2A

Resistance becomes R'

So,

P=R'2A/l/2

= 4R'A /l ---------- (2)

Now we know that resistivity of a wire never get affected by change in shape and size. So,

Eqn- (1) = Eqn- (2)

4A/l = 4 R'A/l

1 = R'

Hence new resistance is 1 ohm

- 1

We know,

P=RA/l

where p is resistivity

R is resistance

A is area of Cross section

l is length of conductor

Wire is of 4 ohm so,

Initially p= 4A /l

When wire is doubled then,

Length get halved i.e l/2

Area get doubled i.e 2A

Let new resistance be R's

So, p'= R'2A/l/2 = 4R'A/l

Now we know that resistivity of a same wire is not depends on resistance. So, if here resistance varies then it is not necessary that the resistivity also changes.

P' = P

4A / l = 4R'A/ l

R' = 1

Hence new resistance is 1 ohm

P=RA/l

where p is resistivity

R is resistance

A is area of Cross section

l is length of conductor

Wire is of 4 ohm so,

Initially p= 4A /l

When wire is doubled then,

Length get halved i.e l/2

Area get doubled i.e 2A

Let new resistance be R's

So, p'= R'2A/l/2 = 4R'A/l

Now we know that resistivity of a same wire is not depends on resistance. So, if here resistance varies then it is not necessary that the resistivity also changes.

P' = P

4A / l = 4R'A/ l

R' = 1

Hence new resistance is 1 ohm

- 0

Dear Student,

In this query we consider wire double on it means to fold the length of wire. It means its length will get half and area of cross section will get double.

Let the resistance of the wire originally 'R' of length 'l' and area of cross-section 'A' with resistivity of material is '?', Then

?

Now, for new arrangement,

?

In this query we consider wire double on it means to fold the length of wire. It means its length will get half and area of cross section will get double.

Let the resistance of the wire originally 'R' of length 'l' and area of cross-section 'A' with resistivity of material is '?', Then

?

Now, for new arrangement,

?

- 0