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Dimensional Formula of Angular Speed

Though angular speed and angular velocity are similar, they are different quantities. It is because you can describe angular speed only with magnitude without showing its direction.

Angular speed is defined as the rate of change of angular distance (i.e., =  θ/T). Usually measured in radian per seconds.

Dimensions – these are mathematical measurements for a particular quantity or measure. These give a simplified understanding of the quantity we are measuring. We use many objects in our everyday life. They all have dimensions of their own. 

Dimensional formula – each quantity can be expressed by means of power (fundamental units) to each unit for derived quantity. The expression can be simply written as,

A= [MpLqTr]

A, p, q and r are constants, and their values differ with each measure. 

 

Dimensional formula: 

In terms of dimensions, a dimensional formula is an equation that expresses the relationship between fundamental and derived units (equation). The letters L, M, and T represent the three basic dimensions of length, mass, and time in mechanics.

All physical quantities can be stated in terms of the fundamental (base) units of length, mass, and time, multiplied by some factor (exponent).

The dimension of the amount in that base is the exponent of a base quantity that enters into the expression.

The units of fundamental quantities are expressed as follows to determine the dimensions of physical quantities:

  • ‘L’ stands for length, 

  • ‘M’ for mass, and 

  • ‘T’ for time.

Example: The area is equal to the sum of two lengths. As a result, [A] = [L2]. An area has two dimensions of the length and zero dimensions of mass and time. In the same way, the volume is the sum of three lengths. As a result, [V] = [L3]. The volume dimension has three dimensions: length, mass, and time.

Dimensions of angular speed:

The dimensions of =  θ/T can be written as 

θ= positive angle – which has no units, so it is dimensionless. So its dimensions are M0L0T0

T= stands for time- which has only one dimension (T); the power to time T is 1 because it is singular, so the dimensions of time T are M0L0T-1

Coming to the dimensions of angular speed- the formula as you already know is =  θ/T, so the dimensions can be written as 

M0L0T0M0L0T1 = 1T1 = T-1

So, the dimensions of angular speed can be written as M0L0T-1 as mass and length are absent their power is ‘0’, and the dimension time is in the denominator which can be written as T-1 mathematically.

Angular speed example: An example of angular speed is a roulette ball on a roulette wheel, a race car on a circular circuit, or a Ferris wheel. In addition, the angular speed of an object is its angular displacement for time.

Another most important example is the angular speed of earth- which is 1.99 x 10-7 rad/sec. So the dimensional formula of This can be written as M0L0T-1

 

Angular speed in real-life examples

  1. When a film tape has rotated the speed of the video reeling out is calculated by angular speed.

  2. We know that all the planets on the solar system rotate in their axis around the sun. The speed of each planet is calculated by means of angular speed. The angle of inclination and time taken for each rotation or spin are measured, and the speed is derived.

  3. The speed of the cycle is measured with the use of angular speed.

  4. The speed of the giant wheel might seem to be slow when seen from the standard public view but the speed of the giant wheel is high when sitting in one of the compartments. And speed/speed is calculated by angular speed.

  5. Can be observed in CD players. The rotation and the spin speed are pre-calculated based on the angular speed.


Conclusion: 

The angular speed is the pace at which an item rotates or circles around an axis, or the rate at which the angular displacement between two bodies varies. This is a scalar quantity. Usually angular speed is measured in radian per seconds. The dimensions of angular speed can be written as [M0L0T-1].

 

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