It is based on the principle of homogeneity. According to this principle, both sides of an equation must be the same.
L.H.S = R.H.S
It also states that only those physical quantities can be added or subtracted which have the same dimensions.
If the dimension of each term on both sides is the same, then the equation is dimensionally correct, otherwise not.
A dimensionally correct equation may or may not be physically correct.
| Exam | Chapter |
| JEE MAIN | Physics and Measurement |
The force of interaction between two atoms is given by ; where x is the distance, k is the Boltzmann constant and T is temperature and
and
are two constants. The dimensions of
is:
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Which of the following relations is dimensionally correct
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An expression of energy density is given by , where
are constants,
is displacement,
is Boltzmann constant and
is the temperature. The dimensions
will be:
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Which of the following equations is dimensionally incorrect?
,
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Which of the following relation is incorrect ?
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Consider the efficiency of Carnot's engine is given by , where
are constants. If
is temperature,
is Boltzmann constant,
is angular displacement and
has the dimensions of length. Then, choose the incorrect option
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Dimensional formula is equal to dimensional formula of
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The equation of a circle is given by , where
is the radius. The equation is modified to change the origin other than
, then find out the correct dimensions of
and
in a new equation
: . The dimensions of
is given as
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Applying the principle of homogeneity of dimensions, determine which one is correct. where $\mathrm{T}$ is time period, $\mathrm{G}$ is gravitational constant,
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Direction: In the following question, a statement of Assertion (A) is followed by a statement of reason (R). Mark the correct choice as:
Assertion: The equation $P=2Q+R$ can not be true if P and Q are velocity and R is distance.
Reason: Quantities with different dimensions can not be added or subtracted.
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The equation of wave is given by Y=ASinω{(x/v)-k}, where ω is the angular velocity and v is the linear velocity. The dimensions of k is
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If a quantity $Q$ is given by $Q=\left(\frac{\mu_0 L^2}{\varepsilon_0 \cdot R \cdot \rho \sqrt{L_0 C}}\right)$
Where,
$\mu_0=$ permeability of a free space, $R=$ resistance, $\rho=$ resistivity, $\mathrm{L}_0=$ inductance, $\mathrm{C}=$ capacitance, $L=$ length
Then what is the dimension of Q in terms of $\mu_0 $ and $\varepsilon_0$:
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If force (F), length (L), and mass (M) are assumed to be fundamental units, then the dimensional formula of the time will be:
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If L = Inductance, C= capacitance, R = Resistance. Then dimension of time is given by:
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If $V=$ Velocity of particle and kinetic energy of particle depends on $V$ as $K \cdot E=\frac{A V^3}{V+B^2} $ , then dimension of $\left[\frac{A}{B}\right]$ is:
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In terms of $\mathrm{R}, \mathrm{T}$, the dimension of $\frac{\mu_0}{R}$ is given as:
(where $\mathrm{R}=$ resistance ,$\mathrm{T}=$ time, $\mu_0=$ Permeability of free space, $\varepsilon_0=$ Permittivity of free space)
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If P, Q, and R are physical quantities, having different dimensions, which of the following combinations can never be a meaningful quantity?
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Which of the following relation is dimensionally correct -
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The energy $E$ and momentum $p$ of a moving body of mass $m$ are related by some equation. Given that c represents the speed for light, identify the correct equation.
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The position of a particle moving on $x$-axis is given by $x(t)=A \sin t+B \cos ^2 t+C t^2+D$, where $t$ is time. The dimension of $\frac{A B C}{D}$ is-
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