Scalars And Vectors MCQ - Practice Questions with Answers

1. Scalars

Physical quantities which can be described completely by its magnitude only but no particular direction.

example- Distance, speed, work, etc.

Tips for scalars-

• Scalars are always positive.

• Represented by alphabet only A, B, C.

• These physical quantities follow normal algebraic rules of addition.

2.  Vectors

Physical quantities can be described by their magnitude and direction.

Physical quantities like Displacement, force, velocity,y etc. are vectors.

Tips for vectors-

• Vectors can be positive, negative, and zero.

• Represented bythe  alphabet having an arrow on their head.

        $\vec{A}, \vec{B}, \vec{C}$

•   These physical quantities follows law of vector addition.

•  Types of vectors

1.  Equal vectors-

Two vectors are said to be equal if they have equal magnitude and the same directions.

                $\begin{aligned} & -\vec{A} \\ & -\vec{B}\end{aligned}$

$
\vec{A}=\vec{B}
$
The angle between these two vectors $\Theta$ is equal to zero.

2. Negative vectors-

      Two vectors are said  to be negative with respect to each other if they have equal magnitude but opposite directions.

$\begin{aligned} & \rightarrow \vec{A} \\ & \leftarrow \vec{B} \\ & \vec{A}=-\vec{B}\end{aligned}$

       Angle between negative vectors is equals to 180 .  i.e $\Theta=180^{\circ}$

3.  Collinear vectors-

    Two vectors are said  to be collinear if they have common line of action.

a. If two vectors are collinear and parallel then the angle between them is zero.

b. If two vector are collinear and anti - parallel then the angle between them is 180⁰.

  So,the  Angle between collinear vectors A & B is either zero or 180⁰. 

                                                              i.e;   $\Theta=0^{\circ}$ or $180^{\circ}$

4. Co-initial vectors-

Two vectors are said to be Co-initial vectors if they have the same initial point.