Introduction to What is Magnitude in Physics?

What is magnitude in Physics, is certainly a question of immense importance in science. Magnitude generally refers to the quantity or distance. In relation to the movement, we can correlate magnitude with the size and speed of the object while travelling.

The size of the object or the amount is its magnitude. Like in case of speed, a car is travelling faster than a motorbike. In this case, the magnitude of the speed of the car is more than that of motorbike. Now, let us discuss what is magnitude in physics.

What is Magnitude in Physics When it Comes to Scalar Quantity

We have basically two types of quantity- scalars and vectors. Both of them have a magnitude in common. Scalar quantities have specific magnitude with the proper unit. Some of the scalar quantities are mass of an object, temperature of a body, time of the event, and the distance between the two points.

We can combine their magnitudes with the ordinary rule of algebra having the same unit. We can add, subtract, divide and multiply the magnitudes of scalar quantity, just as the ordinary number.

Let us look at an example – we have three sides of a triangle as 10m, 8m, and 6m. Then its perimeter will be the sum of its three sides, 10m+8m+6m = 24m. We add only the magnitudes and unit remains the same. Similarly, if we need to find the temperature difference between two bodies, we simply subtract the magnitudes of temperature.

How to Calculate Magnitude of a Vector?

Vector quantities too have magnitude with direction. Some of the vector quantities are – displacement, velocity, acceleration, force, etc. We call the magnitude of a vector as its absolute value.

We can determine that two vectors will only be equal if both have the same magnitude as well as direction. If we multiply a vector with a positive number, its magnitude will change but the direction remains the same. Similarly, if we multiply a vector with a negative number, its magnitude and direction both will change.

What is Magnitude in Physics When it Comes to an earthquake

During the earthquake, energy is released producing seismic waves, which travels in all directions causing vibrations. The magnitude of an earthquake provides the information which is helpful in calculating the probability in times to come. Magnitude is the quantitative value of seismic energy.

It is a specific value having no relation with distance and direction of the epicentre. We can say that magnitude is the size of an earthquake. We measure the magnitude with the help of the Richter scale. Charles. F. Richter invented it in 1934.

This scale measures the largest magnitude of seismic waves without taking into account the type of wave. It is a logarithmic scale in which magnitude increases 10 times with each increase in number.