Question

Question 4.5 Read each statement below carefully and state with reasons, if it is true or false:

(a) The magnitude of a vector is always a scalar, (b) each component of a vector is always a scalar, (c) the total path length is always equal to the magnitude of the displacement vector of a particle. (d) the average speed of a particle (defined as total path length divided by the time taken to cover the path) is either greater or equal to the magnitude of average velocity of the particle over the same interval of time, (e) Three vectors not lying in a plane can never add up to give a null vector.

Chapter Motion In A Plane Page 85

Answer 1

(A) yes !! Magnitude of vector means modulus of vector e.g pure number .

(B) No !! This is false because component of a vector is also vector .

(C) false , this is true only for linear motion of particle .

(D) off- course it is true !!
Because total displacement ≤total distance
So, average speed ≥ average velocity.

(E) yeah !! True , three vectors not lying in a plane can never represent three sides of traingle taken in the same order. Hence give a null vector .