Log out Go to App
Go to App

Learning Materials

Features

Discover

Chapter 26: Q72P (page 770)

A steel trolley-car rail has a cross-sectional area of56.0cm2. What is the resistance of 10.0 kmof rail? The resistivity of the steel is3.00×10-7Ωm.

Short Answer

Expert verified

The resistance of 10km rail is 0.536Ω.

Step by step solution

01

The given data

a) Cross-sectional area,A=56.0×10-4m2

b) Resistivity,ρ=3.00×10-7Ω.m

c) The length of the rail,L=10.0×103m

02

Understanding the concept of the resistance

If a steel trolley car rail moves with its speed having a particular cross-section area, we can find the resistance of that rail by considering the formula for resistance R= ρL/A, where, is the resistivity of the steel and L is the distance traveled by rail and A is its cross-sectional area.

Formulae:

The resistance value of a material, R=ρLA (i)

03

Calculation of the resistance

Using the given data in equation (i), we can get the value of the resistance of the rail as follows:

R=3.00×10710×10356.0×10-4=0.536Ω

Hence, the value of the resistance is 0.536Ω.

Unlock Step-by-Step Solutions & Ace Your Exams!

  • Full Textbook Solutions

    Get detailed explanations and key concepts

  • Unlimited Al creation

    Al flashcards, explanations, exams and more...

  • Ads-free access

    To over 500 millions flashcards

  • Money-back guarantee

    We refund you if you fail your exam.

Start your free trial

Over 30 million students worldwide already upgrade their learning with Vaia!

One App. One Place for Learning.

All the tools & learning materials you need for study success - in one app.

Get started for free

Most popular questions from this chapter

A resistor with a potential difference of 200 V across it transfers electrical energy to thermal energy at the rate of300 V. What is the resistance of the resistor?

In Figure, current is set up through a truncated right circular cone of resistivity 731Ω.m, left radius a = 2.00mm, right radius b = 2.30mm, and lengthL = 1.94 cm. Assume that the current density is uniform across any cross section taken perpendicular to the length. What is the resistance of the cone?

A 120 Vpotential difference is applied to a space heater whose resistance is 14Ωwhen hot. (a) At what rate is electrical energy transferred to thermal energy? (b) What is the cost for 5.0h at US $0.05/kW.h?

Figure 26-18, shows plots of the current Ithrough a certain cross section of a wire over four different time periods. Rank the periods according to the net charge that passes through the cross section during the period, greatest first.

Figure-ashows a rod of resistive material. The resistance per unit length of the rod increases in the positive direction of the xaxis. At any position xalong the rod, the resistancedRof a narrow (differential) section of width dxis given by dR = 5.00 xdx, whereis in ohms and xis in meters. Figure-bshows such a narrow section. You are to slice off a length of the rod between x = 0 and some positionx = Land then connect that length to a battery with potential difference V = 5.0V(Figure-c). You want the current in the length to transfer energy to thermal energy at the rate of 200 W. At what position x = Lshould you cut the rod?
See all solutions

Recommended explanations on Physics Textbooks

Classical Mechanics

Read Explanation

Work Energy and Power

Read Explanation

Modern Physics

Read Explanation

Fluids

Read Explanation

Translational Dynamics

Read Explanation

Solid State Physics

Read Explanation
View all explanations

What do you think about this solution?

We value your feedback to improve our textbook solutions.

Study anywhere. Anytime. Across all devices.

Sign-up for free