# HSC Physics Introduction To Vectors

Contents

**Vector Details** with Diagram

Today, I am going to explain some of the topics from the Higher Secondary Physics chapter Vector. We are going to cover some of the main questions and significant sections of the chapter Vectors.

There are two types of quantities in the world. Vector Quantities and Scalar Quantities. You might what are those?

Scalar quantities:

Those physical quantities have the only magnitude, but no direction, are called Scalar quantities. For Example, mass, time, length, work, density, stress, etc. are scalar quantities.

Vector Quantities:

Those physical quantities have both magnitude and direction are called vector quantities. For examples Velocity, acceleration, displacement, weight etc are vector quantities.

*Difference between Scalar Quantities and Vector Quantities***:**

*Difference between Scalar Quantities and Vector Quantities*

Sl. No |
Scalar quantity |
Vector quantity |

1. | Those physical quantities have the only magnitude, but no direction, are called scalar quantities | . The physical quantities have both magnitude and direction, are called vector quantities. |

2. | Mass, time, length, work, density, stress, etc. are examples of scalar quantities. | Velocity, acceleration, displacement, weight etc are examples of vector quantities. |

3. | It can be added by general algebraic rule. | It cannot be added by general algebraic rule. |

4. | The dot product of two vectors is a scalar quantity. | The cross product of two vectors is a vector quantity. |

5. | If one or both the scalar quantities are not zero, the product can never be zero. | If one or both the vector quantities are not zero, the product may be zero. |

6. | The resultant of two scalar quantities acting at a point making an angle cannot be determined by Parallelogram Law. | The resultant of two scalar quantities acting at a point making an angle can be determined by Parallelogram Law. |

We need to know some other types of vectors too. To fully cover the chapter

*Unit Vector ***:**

If the module of a vector is one (unit), the vector is called unit vector Or**, **A vector having unit magnitude is called a unit vector. Any non-zero vector having its module other than zero gives rise to a unit vector directed along the same direction as the vector. When a non-zero vector quantity is divided by its magnitude, the unit vector is obtained.

*Zero or Null Vector***:**

*Zero or Null Vector*

If the magnitude of a vector is zero, it is called *Zero or* null vector. In other words, a vector whose two endpoints of a directed line segment coincide is known as null or zero vector. If A = B, then A – B = 0, is a null or zero vector.

*Like Vector or parallel vector***:**

Two or more vectors of same nature parallel to one another and directed. In the same direction, are known as **like vectors. **

*Unlike Vector***:**

Two or more vectors of same nature parallel to one another but the directions are in opposite, are known as, **unlike vectors. **

*Co-linear Vector ***:**

If two or more vectors are directed along the same line or parallel to one another, then the vectors are called** Co-linear Vectors.**

#### Position Vector or Radius vector:

Any vector representing the position of a particle with respect to a reference point of a reference frame is known as **position vector or, ****Radius vector.**

*Rectangular Unit Vector **:*

A set of unit vectors in three-dimensional rectangular coordinate systems directed Along the positive X, Y and Z axes denoted by I, are called rectangular unit vector.