A negligibly small current is passed through a wire of length 15 m and uniform cross-section 6.0 × 10−7 m2, and its resistance is measured to be 5.0 Ω. - Physics

Advertisements
Advertisements
Numerical

A negligibly small current is passed through a wire of length 15 m and uniform cross-section 6.0 × 10−7 m2, and its resistance is measured to be 5.0 Ω. What is the resistivity of the material at the temperature of the experiment?

Advertisements

Solution

Length of the wire, l = 15 m

Area of cross-section of the wire, a = 6.0 × 10−7 m2

Resistance of the material of the wire, R = 5.0 Ω

Resistivity of the material of the wire = ρ

Resistance is related to resistivity as

R = `ρ "l"/"A"`

ρ = `("RA")/"l"`

= `(5 xx 6 xx 10^-7)/15`

= 2 × 10−7 Ω m

Therefore, the resistivity of the material is 2 × 10−7 Ω m.

  Is there an error in this question or solution?
Chapter 3: Current Electricity - Exercise [Page 127]

APPEARS IN

NCERT Physics Class 12
Chapter 3 Current Electricity
Exercise | Q 3.6 | Page 127
NCERT Physics Class 12
Chapter 3 Current Electricity
Exercise | Q 6 | Page 127

Video TutorialsVIEW ALL [1]

RELATED QUESTIONS

At room temperature (27.0°C) the resistance of a heating element is 100 Ω. What is the temperature of the element if the resistance is found to be 117 Ω, given that the temperature coefficient of the material of the resistor is 1.70 × 10−4 °C−1.


A silver wire has a resistance of 2.1 Ω at 27.5°C, and a resistance of 2.7 Ω at 100°C. Determine the temperature coefficient of resistivity of silver.


A heating element is marked 210 V, 630 W. What is the value of the current drawn by the element when connected to a 210 V dc source?


A heating element is marked 210 V, 630 W. Find the resistance of the element when connected to a 210 V dc source.


Two wires of equal length, one of copper and the other of manganin have the same resistance. Which wire is thicker?


Two resistors A and B have resistances RA and RB, respectively, and RA < RB. The resistivities of their materials are ρA and ρB.


A wire of length 1 m and radius 0.1 mm has a resistance of 100 Ω. Find the resistivity of the material.


A uniform wire of resistance 100 Ω is melted and recast as a wire whose length is double that of the original. What would be the resistance of the wire?


What length of a copper wire of cross-sectional area 0.01 mm2 will be needed to prepare a resistance of 1 kΩ? Resistivity of copper = 1.7 × 10–8 Ωm


The electrochemical equivalent of a material depends on _______________ .


If R1 and R2 are filament resistances of a 200 W and a 100 W bulb respectively, designed to operate on the same voltage, then:


A strip of copper and another of germanium are cooled from room temperature to 80 K. The resistance of ______.

Fuse wire should have


If the last band on the carbon resistor is absent, then the tolerance is ______


Share
Notifications



      Forgot password?
Use app×