Physical Quantities: SCALAR and Vector Physics

Physical Quantities: SCALAR and Vector Physics: Quantity refers to everything that can be measured or stated numerically in the physical world. Assume an item has a length of one meter and a mass of five kg. The item is travelling at a speed of 10 meters per second from east to west.

[ Physical Quantities: SCALAR and Vector Physics ]

Each of the numbers stated here may be represented numerically. Both values and directions must be given in some circumstances. For example, if an object’s length is 1 meter, it measures 1 meter from one end to the other, and it measures 1 meter from the other end, therefore measuring from one end or the other here will not change the length. Similarly, an object’s mass, which reflects the overall amount of substance contained in the thing, does not necessitate any examination of its expression or appearance.

However, the direction in which the object is going at a speed of 10 meters per second is important. The object’s final location will change if it goes from east to west, but its final location will not be the same as before if it moves to any other side. As a result, it is clear that certain quantities rely just on value, whereas others require both value and direction to be represented.

 

Scalar sums are sums that may be written entirely in terms of numbers, do not require any direction, and change only by altering the value. Energy, mass, length, distance, pressure, work, and other scalar values are examples.
Quantities that cannot be fully expressed by values alone, require both value and direction for the full expression of the sums and alter the value only by changing the value or merely the direction or both, are called vector. Displacement, velocity, acceleration, weight, force, intensity, etc. are some examples of vectors. 

In the case of scalar quantities, it is possible to perform mathematical operations correctly by following the rules of simple algebraic addition, subtraction and division. Because the angle between two or more signs, their location, and direction have no influence in this scenario. As a result, algebraic principles may be applied to the addition or subtraction of two or more scalar numbers, as well as the work of any mathematical operator.

Karim and Rahim, for example, are in a vehicle. One of them is 50 kilograms and the other is 60 kg. The total mass of the two will be (50 + 60) kg = 120 kg. Note that the addition and subtraction of two or more scalar quantities is the result obtained and the scalar.

 

Vector quantities are not subject to general algebraic laws. The intermediate angle affects the result of the activity conducted between them by changing the value and direction of each of the two or more vector values. To add vectors, formulae such as triangle formula, polygonal formula, and parallelogram formulas are employed. None of the rules for algebraic addition will provide similar results. 

If a scalar quantity is multiplied to the vector quantity, it gives a result of which is another vector quantity. Moreover, when a vector is multiplied with another vector, there can be two different kind of multiplication process. One is called dot multiplication and another one is cross multiplication. The result of dot multiplication is scalar and the result of cross multiplication is vector।

 

There are some differences between scalar and vector quantities. The scalar quantities do not have directions like the vectors. Every scalar quantities are one-dimensional whereas vector quantities can be 1-D, 2-D, or 3-D.
Scalar quantity can be resolved as it has the exact same value regardless of the direction. Vector can be resolved in any direction using sine or cosine or the adjacent angle. 

Read more:

• Vector Physics and its Classification
• Dot and cross multiplication of vector and its application
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