Access free live classes and tests on the app
Download
+
Unacademy
  • Goals
    • AFCAT
    • AP EAMCET
    • Bank Exam
    • BPSC
    • CA Foundation
    • CAPF
    • CAT
    • CBSE Class 11
    • CBSE Class 12
    • CDS
    • CLAT
    • CSIR UGC
    • GATE
    • IIT JAM
    • JEE
    • Karnataka CET
    • Karnataka PSC
    • Kerala PSC
    • MHT CET
    • MPPSC
    • NDA
    • NEET PG
    • NEET UG
    • NTA UGC
    • Railway Exam
    • SSC
    • TS EAMCET
    • UPSC
    • WBPSC
    • CFA
Login Join for Free
avtar
  • ProfileProfile
  • Settings Settings
  • Refer your friendsRefer your friends
  • Sign outSign out
  • Terms & conditions
  • •
  • Privacy policy
  • About
  • •
  • Careers
  • •
  • Blog

© 2023 Sorting Hat Technologies Pvt Ltd

Watch Free Classes
    • Free courses
    • JEE Main 2024
    • JEE Main 2024 Live Paper Discussion
    • JEE Main Rank Predictor 2024
    • JEE Main College Predictor 2024
    • Stream Predictor
    • JEE Main 2024 Free Mock Test
    • Study Materials
    • Notifications
    • JEE Advanced Syllabus
    • JEE Books
    • JEE Main Question Paper
    • JEE Coaching
    • Downloads
    • JEE Notes & Lectures
    • JEE Daily Videos
    • Difference Between
    • Full Forms
    • Important Formulas
    • Exam Tips
JEE Main 2026 Preparation: Question Papers, Solutions, Mock Tests & Strategy Unacademy » JEE Study Material » Physics » Dimensional Formula of Linear Density

Dimensional Formula of Linear Density

This article contains explanations of linear density and linear charge density, their usage in particular fields, surface density and the dimensional formula of linear density with derivation.

Table of Content
  •  

Linear density along with the linear charge density are two tools used in science and engineering. The unit per length measurement of the characteristics of any quantity is termed linear density. Linear mass density is the value of mass distributed in unit length, and linear charge density is the value of electric charge in one unit length used in fields of science and engineering. Thus, it defines their importance in their respective fields. The properties of 1-D objects and the density of a three-dimensional quantity along a single dimension can be determined using a linear density. 

Dimensional formula of linear density

The dimensional formula of linear density can be written as [M1L-1T0].

Derivation of the dimensional formula of latent heat:

Linear Density (ρ) = (Mass). 1 / (Length)

(ρ) = m / L …(i)

  • Dimensional formula of mass:

 [M1L0T0] …(ii)

  • Dimensional formula of length:

 [M0L1T0] …(iii)

Putting values of equations (ii) and (iii) in equation (i).


Therefore, Linear Density = (Mass). 1 / (Length)

ρ = [M1L0T0]. [M0L1T0]-1 = [M1L-1T0]

Hence, the linear density can dimensionally be represented as:

[M1L-1T0]

Dimensional Analysis

Dimensional analysis is the process of determining the dimensions of physical quantities to verify their relationships. These dimensions are unrelated to numerical multiples and constants, and any quantity in the world can be expressed as a function of these 7 fundamental dimensions.

Dimensional analysis studies the relationship between physical quantities using dimensions and units of measurement. Dimensional analysis is critical because it maintains the same units, enabling us to perform mathematical calculations efficiently.

Unit Conversion and Dimensional Analysis

Dimensional analysis is also called the Factor Label Method or Unit Factor Method because it employs conversion factors to obtain the same units. To illustrate the statement, suppose you want to know how many metres make up 3 kilometres.


We know that 1000 metres equals 1 km; thus, 3 km equals 3 × 1000 metres, which is 3000 metres. The conversion factor is 1000 metres in this case.

Dimensional Analysis as a Tool for Verifying the Correctness of Physical Equations

  • Assume you’re unsure whether time equals speed/distance or distance/speed.
  • This can be verified by comparing the dimensions on both sides of the equations.
  • We obtain this by reducing both equations to their fundamental units on each side of the equation.
  • However, it is worth noting that dimensional analysis cannot be used to determine any dimensionless constants in the equation.

Conclusion

The characteristic trait of any object per unit of length is called linear density. If the concentration of the density is the same, it is called uniform linear density; and if it is irregular, then the calculations of the traits become tough. The density of the object affects the speed of the wave; i.e. if the concentration of density is high, the wave speed will be slow and vice versa. Thus, it follows the principles of inverse proportionality. The linear density is a per unit length measurement, whereas the surface density is a per unit volume measurement of the character of any quantity.

faq

Frequently Asked Questions

Get answers to the most common queries related to the JEE Examination Preparation.

Find the linear mass density of the carbon steel string? Assuming 0.80 mm diameter carbon steel string of density = 7.860 g/cm3.

The answers need to be solved in the following steps. ...Read full

Define linear density and surface density.

The linear density is termed the unit per length measurement of the cha...Read full

Define wave speed relation with linear density.

The speed of the wave will be higher for the lower concentration of the density; i.e., the relation follows the prin...Read full

What does the uniform linear density explain?

The uniform linear density explains the distribution of the concentrati...Read full

What are dimensionless quantities?

Dimensionless quantities are physical quantities that lack dimensions. ...Read full

What are the fundamental principles of dimensional analysis?

Dimensional analysis is only conceivable if the dimensions of the individual terms on both sides of the equation are...Read full

The answers need to be solved in the following steps.

  • Step 1: The volume of the length of the string. (Taking l = 1m = 100cm)

V = (π). (r)2. (l) …(i)

  • The radius = D / 2. 
  • Therefore, r= 0.80 mm = 0.40 mm = 0.040 cm …(ii)

V = (π). (r)2. (l) = π . (0.040 cm)2. (100 cm) = 0.503 cm3 …(iii)

  • Step 2: Find the mass of the wire.

Mass = (0.503 cm3). (7.860 g/cm3) = 3.95 g …(iv)

  • Step 3: Find the linear mass density.

Putting the values of equations (iii) and (v)

Linear mass density = mass / length= (3.95 g) / (1m) = 4.0 g/m

The linear density is termed the unit per length measurement of the characteristics of any quantity, whereas the unit per volume measurement of any quantity is termed as surface density. 

The speed of the wave will be higher for the lower concentration of the density; i.e., the relation follows the principles of inverse proportionality as the square root of the linear mass density is inversely proportional to wave speed.

The uniform linear density explains the distribution of the concentration of the density of mass at each per unit length of an object.

Dimensionless quantities are physical quantities that lack dimensions.

For instance, angle, specific gravity, and strain.

Dimensional analysis is only conceivable if the dimensions of the individual terms on both sides of the equation are the same. This is referred to as the principle of dimensional homogeneity. The concept is founded on the observation that two quantities of the same dimension may only be added, subtracted, or compared.

Crack IIT JEE with Unacademy

Get subscription and access unlimited live and recorded courses from India’s best educators

  • Structured syllabus
  • Daily live classes
  • Ask doubts
  • Tests & practice
Learn more

Notifications

Get all the important information related to the JEE Exam including the process of application, important calendar dates, eligibility criteria, exam centers etc.

Allotment of Examination Centre
JEE Advanced Eligibility Criteria
JEE Advanced Exam Dates
JEE Advanced Exam Pattern 2023
JEE Advanced Syllabus
JEE Application Fee
JEE Application Process
JEE Eligibility Criteria 2023
JEE Exam Language and Centres
JEE Exam Pattern – Check JEE Paper Pattern 2024
JEE Examination Scheme
JEE Main 2024 Admit Card (OUT) – Steps to Download Session 1 Hall Ticket
JEE Main Application Form
JEE Main Eligibility Criteria 2024
JEE Main Exam Dates
JEE Main Exam Pattern
JEE Main Highlights
JEE Main Paper Analysis
JEE Main Question Paper with Solutions and Answer Keys
JEE Main Result 2022 (Out)
JEE Main Revised Dates
JEE Marking Scheme
JEE Preparation Books 2024 – JEE Best Books (Mains and Advanced)
Online Applications for JEE (Main)-2022 Session 2
Reserved Seats
See all

Related articles

Learn more topics related to Physics
Zinc-Carbon Cell

The battery you use every day in your TV remote or torch is made up of cells and is also known as a zinc-carbon cell. Read on to know more.

ZEROTH LAW OF THERMODYNAMICS

Read about the Zeroth law of thermodynamics. Learn about the zeroth law definitions and their examples.

Zener Diode As A Voltage Regulator

Understand the concepts of Zener diodes. Also, learn about the efficiency and limitations of Zener Diode as a Voltage Regulator.

Zener diode as a voltage regulator

zener diode is a very versatile semiconductor that is used for a variety of industrial processes and allows the flow of current in both directions.It can be used as a voltage regulator.

See all
Access more than

10,505+ courses for IIT JEE

Get subscription

Trending Topics

  • JEE Main 2024
  • JEE Main Rank Predictor 2024
  • JEE Main Mock Test 2024
  • JEE Main 2024 Admit Card
  • JEE Advanced Syllabus
  • JEE Preparation Books
  • JEE Notes
  • JEE Advanced Toppers
  • JEE Advanced 2022 Question Paper
  • JEE Advanced 2022 Answer Key
  • JEE Main Question Paper
  • JEE Main Answer key 2022
  • JEE Main Paper Analysis 2022
  • JEE Main Result
  • JEE Exam Pattern
  • JEE Main Eligibility
  • JEE College predictor
combat_iitjee

Related links

  • JEE Study Materials
  • CNG Full Form
  • Dimensional Formula of Pressure
  • Reimer Tiemann Reaction
  • Vector Triple Product
  • Swarts Reaction
  • Focal length of Convex Lens
  • Root mean square velocities
  • Fehling’s solution
testseries_iitjee
Subscribe Now
. document.querySelector('.targetTopBtn').onClick = topFunction; function topFunction() { window.scrollTo({ top: 0, behavior: 'smooth' }) }
Company Logo

Unacademy is India’s largest online learning platform. Download our apps to start learning


Starting your preparation?

Call us and we will answer all your questions about learning on Unacademy

Call +91 8585858585

Company
About usShikshodayaCareers
we're hiring
BlogsPrivacy PolicyTerms and Conditions
Help & support
User GuidelinesSite MapRefund PolicyTakedown PolicyGrievance Redressal
Products
Learner appLearner appEducator appEducator appParent appParent app
Popular goals
IIT JEEUPSCSSCCSIR UGC NETNEET UG
Trending exams
GATECATCANTA UGC NETBank Exams
Study material
UPSC Study MaterialNEET UG Study MaterialCA Foundation Study MaterialJEE Study MaterialSSC Study Material

© 2026 Sorting Hat Technologies Pvt Ltd

Unacademy
  • Goals
    • AFCAT
    • AP EAMCET
    • Bank Exam
    • BPSC
    • CA Foundation
    • CAPF
    • CAT
    • CBSE Class 11
    • CBSE Class 12
    • CDS
    • CLAT
    • CSIR UGC
    • GATE
    • IIT JAM
    • JEE
    • Karnataka CET
    • Karnataka PSC
    • Kerala PSC
    • MHT CET
    • MPPSC
    • NDA
    • NEET PG
    • NEET UG
    • NTA UGC
    • Railway Exam
    • SSC
    • TS EAMCET
    • UPSC
    • WBPSC
    • CFA

Share via

COPY