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Scalar and Vector Point Functions

This write-up is based on the introduction of scalar quantity and vector quantity. Scalar and vector point of functions. Examples of scalar and vector point functions and scalar and vector fields.

Scalar Quantity

A scalar quantity is described as a quantity that has only magnitude but no particular direction. For example – volume, energy, speed, mass, density, and time.

Vector Quantity

Vector quantity is described as a quantity that has both magnitude and direction. For example – force and velocity.

Scalar and Vector Point of Functions

Scalar point functions

A scalar point function is defined as a function which assigns  a real number to every point of a part of the region of space.

If to every point (p, q, r) or z of a region x in space, there is assigned a real number m = Φ(p, q, r), then Φ is called a scalar point function.

Vector Point Functions

A vector point function is defined as a function which assigns  a vector to every point of a part of the region of space.

If to every point (p, q, r ) or z of a region x in space, there is assigned a vector V = V(p, q, r), the V is called a vector point function and the function is represented as:

V = v1 (p, q, r) i + v2 (p, q, r) j +v3 (p, q, r) k

OR,

V = v1      v1 (p, q, r)

      v2  =  v2 (p, q, r)

      v3       v3 (p, q, r)

Examples of Scalar Point Function and Vector Point Function

Examples of Scalar Point Functions are:

  1. If z = (p, q, r) then p2 + q2 + r2 is a scalar point function and it forms a three dimensional scalar field.
  2. If z = (p,q) then (z) = p2+q2 is a scalar point function and it forms a two dimensional scalar field.

Examples of Vector Point Function are:

  1. ∇ = pi + qj + zk is a vector point function, which associates with each point (p, q, r)) a vector pointing away from its origin. This represents a three-dimensional source field.

Scalar Function and Vector Function

Scalar Functions

To set of real variables A scalar Function is that which assigns a real number. It is represented in general form as,

m = m(P1, P2, P3, …, Pn )

Where, P1, P2, P3, …, Pn) can be considered real numbers.

Vector Functions

A vector function is that which assigns a group of real variables to the vector. It is represented in general form as,

V = v1 (P1 , P2, P3, … , Pn) i + v2 (P1 , P2, P3 … , Pn) j + v3 (P1, P2, P3 … , Pn) k

Where, P1, P2, P3, …., Pn can be considered real numbers.

Scalar Field and Vector Field

Scalar field

A Scalar field is a scalar point function that is defined over some region. A scalar field that is not dependent on time is called a  steady-state scalar field or stationary.

A scalar field varying with time is represented as,

m = Φ (p, q, r, t)

Examples of scalar fields are –

  • The temperature at each point in an insulated wall
  • The mass density of the atmosphere
  • The water pressure at each point in an ocean

Vector Field

A Vector field is a vector point function defined over some region. A vector field that is not dependent on time is called a steady-state vector field or stationery.

A vector field varying with time is represented as,

V = v1 (p, q, r, t) i + v2 (p, q, r, t) j + v3 (p, q, r, t)k

Examples of vector fields defined in space are –

  • Magnetic Field
  • Gravitational Field

Conclusion

This is to conclude that a scalar point function is defined as a function which assigns a real number to every point of a part of the region of space and a vector point function is defined as a function which assigns a vector to every point of a part of the region of space.