Velocity and acceleration of a particle at some instant are v =(3 i -4 j +2 k )

PHYSICS · Multi-part · CBSE · Physics · Motion in a Plane · Motion in a Plane

Problem

Velocity and acceleration of a particle at some instant are

\mathbf{v}=(3\hat{i}-4\hat{j}+2\hat{k})\,\text{m/s}\quad\text{and}\quad\mathbf{a}=(2\hat{i}+\hat{j}-2\hat{k})\,\text{m/s}^2.

(a) What is the value of the dot product of

\mathbf{v}

and

\mathbf{a}

at the given instant? (b) Is the angle between

\mathbf{v}

and

\mathbf{a}

acute, obtuse, or

90^\circ

? (c) At the given instant, is the speed of the particle increasing, decreasing, or constant?