Advertisements
Advertisements
Question
What are the limitations of dimensional analysis?
Solution
(1) This method gives no information about the dimensionless constants in the formula. Like 1, 2,7i, e, etc. ie they can not be determined using this analysis.
(2) This method can not decide whether the given quantity is a scalar or a vector.
(3) Using this method one cannot derive relations involving trigonometric, exponential, and logarithmic functions.
(4) It cannot be applied to an equation involving more than three physical quantities.
(5) It can be used to check whether a given physical relation is dimensionally correct or not. The physical correctness can not be checked using this
For example:
s = ut + `1/3` at² is dimensionally correct were as physically not correct, as the correct equation is s = ut + `1/2`at².
APPEARS IN
RELATED QUESTIONS
[L1M1T-2] is the dimensional formula for ______.
Dimensions of kinetic energy are the same as that of ______.
The dimensional formula of Planck's constant h is ______
The velocity of a particle v at an instant t is given by v = at + bt2. The dimensions of b are ______
The dimensional formula for gravitational constant G is ______
If the force is proportional to the square of velocity, then the dimension of the proportionality constant is ______
The dimension of `(mu_0ε_0)^{1/2}` is ______
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?.
Write a short note on the following.
Dimensionless quantities
Assuming that the frequency γ of a vibrating string may depend upon i) applied force (F) ii) length (l) iii) mass per unit length (m), prove that ϒ ∝ `1/lsqrt(F/m)` using dimensional analysis.