Home
Class 10
PHYSICS
A wire of resistivity p is pulled to dou...

A wire of resistivity p is pulled to double its length. What will be its new resistivity?

Text Solution

Verified by Experts

`R=(rhoL)/A`
When L becomes 2L, A becomes A/2
`R=(rho2L)/(A/2)=(4rhoL)/A=4R`
New resistance becomes 4 times the original one. But, resistivity remains the same as it is the property of the substance and does not change with length or area.
Doubtnut Promotions Banner Mobile Dark
|

Topper's Solved these Questions

  • ELECTRICITY

    ZEN PUBLICATION|Exercise ZEN ADDITIONAL QUESTIONS SECTION (SHORT ANSWER TYPE 2 QUESTIONS)|24 Videos

  • ELECTRICITY

    ZEN PUBLICATION|Exercise ZEN ADDITIONAL QUESTIONS SECTION (LONG ANSWER QUESTIONS)|30 Videos

  • ELECTRICITY

    ZEN PUBLICATION|Exercise ZEN ADDITIONAL QUESTIONS SECTION (VERY SHORT ANSWER TYPE QUESTIONS)|42 Videos

  • LIGHT - REFLECTION AND REFRACTION

    ZEN PUBLICATION|Exercise ZEN ADDITIONAL QUESTIONS SECTION (LONG ANSWER [LA] QUESTIONS)|30 Videos

Similar Questions

Explore conceptually related problems

A wire of resistance R is uniformly stretched until its radius is halved. Its new resistance is

A uniform wire of resistance R is uniformly compressed along its length until its radius becomes n times the original radius. Now the resistance of the wire becomes

Knowledge Check

  • A uniform wire of resistance R is stretched uniformly so that its length is doubled. Its new resistance is

    A
    4R
    B
    `R/4`
    C
    `R/2`
    D
    2R

  • A meter bridge is used to determine the resistance of an unknown wire by measuring the balance point length l. If the wire is replaced by another wire of same material but with double the length and half the thickness the balancing point is expected to be :

    A
    `1/(8l)`
    B
    `1/(4l)`
    C
    `8l`
    D
    `16l`

    • Similar Questions

    Explore conceptually related problems

    A uniform wire of resistance 9Omega is bent to form an equilateral triangle. What is the effective resistance between any two corners of the triangle.

    A wire of length I and area of aou-aection A wu dnwn into a wire of double Its length by melting orignial resistivity and resistance were rho and R and resistance ?

    The folllowing reading are obtained in a meter bridge experiment to find the resistivity of the material of a given wire. Calculate the resistivity of the material of the wire. Diameter of the wire =d =0.36 mm, length of the wire L = 60 cm.

    Two resistors are connected in parallel. What will happen to its equivalent resistance?

    A negligbly small current is passed through a wire of length 15m, uniform cross - section 6.0xx10^(-7)m^(2) and its resistance is measured to be 5.0Omega . What is the resistivity of the material at the temperature of the experiment?

    When a metal is heated, its resistance

    Home
    Profile