we can divide physical quantities into 2 part vectors are physical quantities in physics which have both magnitude and direction.While scalars are that quantities which only have magnitude as their sole property. To explain better there is an example a person a is facing towards south he moves towards south for an hour and then takes a turn towards west and the again moves for an hour so he actually distance travelled is 500mi+100mi=600mi which is depicted by the black lines . The actual distance travelled ie 600m is dependent of the path followed and so independent of direction.As if he had travelled straight instead of turning right distance travelled would be same. So it is a scalar quantity now if we are calculating the displacement be the man it is root of 500^2 +100^2 (calculated by phythogoras theoram).Now displacement is the length of path formed by jo...