When we take a measurement of a parameter, the result is always a number. Only when the correct unit is supplied does this number make sense. As a result, a measurement’s result has a numerical value as well as a unit of measurement.
A body’s mass, for example, is 3 kilograms. A quantity with the numerical value 3 and the unit of measurement kg are used in this example. The magnitude is the numerical value combined with the unit. For the comprehensive description of some physical quantities, only magnitude is required. Magnitudes include body mass, distance between two places, time, temperature, height, the number of pendulum swings, and the number of books in a bag. They don’t have any sense of direction. Scalar quantities are those that have a single magnitude for their whole specification.
Other physical quantities, such as displacement, require a direction with magnitude to be described. Consider a body that moves from point X to point Y. The displacement is denoted by the letters XY. When the body moves from Y to X, however, the displacement is YX.
Vectors are quantities that need both magnitude and direction in order to be fully specified. Momentum, force, torque, magnetic field, and other vector quantities are examples.
b=–a
Vertical lines on both sides of the provided vector “|a|” illustrate the magnitude of a vector. It represents the vector’s length. The magnitude of a vector is calculated mathematically using the “Pythagoras Theorem,” i.e., b=x2+y2
One of the vector addition laws is the triangle law of vector addition. Because vectors do not obey ordinary algebraic principles, vector addition is specified as the geometrical combination of two or more vectors. The composition of a vector is the resultant vector.
The laws of vector addition are as follows:
The triangle law of vector addition says that when two vectors are expressed as two sides of a triangle with the same order of magnitude and direction, the direction and magnitude of the resultant vector is represented by the third side of the triangle.
A vector is a mathematical representation of physical quantities that may be calculated in both magnitude and direction. A straight line with an arrowhead represents a vector of any physical quantity. The magnitude of the vector is determined by the length of the straight line, and the direction is determined by the arrowhead. If the magnitude and direction of two vectors are equal, they are considered identical vectors. The force applied to an object is the finest example of a vector since both the strength and direction of the applied force affect the object’s action. A vector’s magnitude will never change if it is rotated or moved around itself.