11. In everyday use and in kinematics, the speed of an object is the magnitude of the rate of change of its position with time or the magnitude of the change of its position per unit of time; it is thus a scalar quantity.
12. Speed is the time rate at which an object is moving along a path, while velocity is the rate and direction of an object's movement. Put another way, speed is a scalar value, while velocity is a vector. In its simplest form, average velocity is calculated by dividing change in position (Δr) by change in time (Δt).
13. Here we will learn the mathematical relation between the speed, distance and time. The speed of a moving body is the distance travelled by it in unit time. If the distance is in km and time is in hours, then the speed is km/hr. If the distance is in m and the time is in seconds, then the speed is m/sec.
14. Average speed is the distance traveled divided by elapsed time. We have noted that distance traveled can be greater than displacement. So average speed can be greater than average velocity, which is displacement divided by time
15. Both have the same average speed, so neither is the fastest. (Please see the solution in the picture)
16. Acceleration is a vector quantity which is defined as the rate at which an object changes its velocity. An object is accelerating if it is changing its velocity.