Dimensional Analysis and Its Applications

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Dimensional Analysis and Its Applications: Overview

In this topic, we will analyse the dimensional formulas and learn its applications. It also describes the principle of homogeneity of dimensions. We will also learn to deduce relations among the physical quantities.

Important Questions on Dimensional Analysis and Its Applications

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The dimensions of  ( μ 0 ε 0 ) 1 2 are

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The dimensions of    ( μ 0 ε 0 ) 1 2 are

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The ratio of the dimensions of Planck’s constant and that of the moment of inertia has the dimensions of

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The force F on a sphere of radius a moving in a medium with velocity v is given by   F=6πηav.  The dimensions of   η  are

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The frequency of vibration f of a mass m suspended from a spring of spring constant k is given by a relation of the type f=cmxky , where c is a dimensionless constant. The values of x and y are:

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If    x=at+b t 2 ,  where x is the distance travelled by the body in kilometres while t is the time in seconds, then the unit of b is:

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Of the following quantities, which one has dimension different from the remaining three?

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Dimensional formula of self inductance is:

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If C and R denote capacitance and resistance respectively, then the dimensional formula of CR is

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Which of  the following is a dimensional constant?

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In a particular system, the unit of  length, mass and time are chosen to be 10 cm. 10 g and  0.1 s respectively. The unit of force in this system will be equivalent to

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P represents radiation pressure, c represents speed of light and S represents radiation energy striking unit area per sec. The non zero integers x, y, z such that  PxSycz is dimensionless are:

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Dimensions of electrical resistance are:

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Pressure depends on distance as P=α β exp-αzkθ, where α,β are constants z is distance, k is Boltzman's constants and θ is temperature. The dimension of β are

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A length-scale (l) depends on the permittivity (ε) of a dielectric material, Boltzmann constant (kB), the absolute temperature (T), the number per unit volume (n) of certain charged particles, and the charge (q) carried by each of the particles. Which of the following expression for l is dimensionally correct?

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In CGS system the magnitude of the force is 100 dyne. In another system, where the fundamental physical quantities are kilogram, metre and minute, the magnitude of the force is

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In the kinematic equation s= ut + (½)at2 , the dimensions of all the three terms is-
 

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Identify a dimensionally correct expression from the following options.

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Choose the physical quantity from the given options that has the same dimensional formula as an impulse.

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A particle of mass m is located in a region where its potential energy U(x) depends on the position x as, Ux=ax2-bx. Here, a and b are positive constants. If the time period of oscillation, which is calculated from above formula, is stated by a student as T=4πamab2, check whether his answer is dimensionally correct.