What is vector and scalar quantities?

Answer 1

A vector quantity is a quantity that has both magnitude and direction. Velocity, acceleration, and force are examples of vector quantities.

A scalar quantity is a quantity that has magnitude, but no direction. Time, mass, volume, and speed are examples of scalar quantities.

Answer 2

In simple terms, a scalar is a quantity such as temperature, pressure, density, mass, energy etc. which can be quantified with a single number. That is, a scalar has a magnitude but no direction.

Similarly, a vector is a quantity such as displacement, velocity, force, electric field etc. which has not only a magnitude but also a direction in space.

Scalars, being ordinary numbers, can be added together, multiplied etc. in the normal way.

The algebra of vectors is a little more complex:

(1) Given two vectors a and b, we can form the sum a + b using the parallelogram law (see the related links).

(2) Given a vector a and a scalar k, we can multiply them to obtain a new vector ka having the same (or directly opposite) direction as a, but with its length multiplied by k. (Note: if k is negative then the new vector's direction is opposite to a's; otherwise the directions are the same.)

(3) Given two vectors, we can form their scalar producta⋅b (also known as the dot product). This is a scalar value, given by the product of the vectors' magnitudes with the cosine of the angle between them. Equivalently, the scalar product is the magnitude of the first vector multiplied by the length of the projection of the second vector onto the first.

(4) Given two vectors, we can also form their vector product a×b (also known as the cross product). This is a vector at right angles to both the original vectors, having a magnitude equal to the product of the original vectors' magnitudes with the sine of the angle between them. There is a subtlety here involving handedness; see the related links for more information.

All of the above operations have practical uses in physics, particularly in Newtonian mechanics and classical electromagnetism.

Answer 3

A scalar quantity only has magnitude (how much). Like Mass. A vector quantity has magnitude and direction. Like Force.


An object being pushed upwards by one Newton of force and from the side by two Newtons of force, for example, might be illustrated with one vector arrow pointing upward from the center of the object and another, twice as long, pointing from the center of the object to the side. Such illustrations are invaluable in physics, because they allow one to apply mathematics (trigonometry, in this case) to determine the resulting force (scalar) and direction (vector).

Answer 4

vector quantity is thyat quantity which hasa magnitudeand direction.e.g area is a vector quantity.it has a magnitude and direction along the perpendicular to the surface of the area

a scalar quantutity is that quantity which has only magnitude.

Answer 5

A scalar quantity is one which has only magnitude. Example: Mass A vector quantity is one which has both magnitude and direction. Example: Weight (It acts downwards)