If force [F], acceleration [A] and time [T] are chosen as the fundamental physical quantities. Find the dimensions of energy
[F] [A−1] [T]
[F] [A] [T]
[F] [A] [T2]
[F] [A] [T−1]
To find the dimensions of energy using the given fundamental physical quantities: Force [F], Acceleration [A], and Time [T], we need to express energy in terms of these quantities.
Energy is typically defined as work done, which can be calculated using the formula:
\(\text{Energy} (E) = \text{Force} (F) \times \text{Distance} (d)\)
We know that:
Also, Velocity \(v\) can be expressed in terms of Acceleration and Time:
\(v = A \times T\)
Substituting this into the distance formula:
\(d = (A \times T) \times T = A \times T^2\)
Thus, Energy becomes:
\(E = F \times d = F \times (A \times T^2) = F \times A \times T^2\)
Therefore, the dimensions of energy in terms of [F], [A], and [T] are:
\([F] [A] [T^2]\)
This matches the provided correct answer option: [F] [A] [T2].
Match the LIST-I with LIST-II
| LIST-I | LIST-II | ||
| A. | Boltzmann constant | I. | \( \text{ML}^2\text{T}^{-1} \) |
| B. | Coefficient of viscosity | II. | \( \text{MLT}^{-3}\text{K}^{-1} \) |
| C. | Planck's constant | III. | \( \text{ML}^2\text{T}^{-2}\text{K}^{-1} \) |
| D. | Thermal conductivity | IV. | \( \text{ML}^{-1}\text{T}^{-1} \) |
Choose the correct answer from the options given below :
Dimensional Analysis is a process which helps verify any formula by the using the principle of homogeneity. Basically dimensions of each term of a dimensional equation on both sides should be the same.
Limitation of Dimensional Analysis: Dimensional analysis does not check for the correctness of value of constants in an equation.
Let us understand this with an example:
Suppose we don’t know the correct formula relation between speed, distance and time,
We don’t know whether
(i) Speed = Distance/Time is correct or
(ii) Speed =Time/Distance.
Now, we can use dimensional analysis to check whether this equation is correct or not.
By reducing both sides of the equation in its fundamental units form, we get
(i) [L][T]-¹ = [L] / [T] (Right)
(ii) [L][T]-¹ = [T] / [L] (Wrong)
From the above example it is evident that the dimensional formula establishes the correctness of an equation.