Question

A person walks first at a constant speed of 5.40 m/s along a straight line from point to point and then back along the line from to at a constant speed of 3.10 m/s. (a) What is her average speed over the entire trip

Answer 1

Answer: The average speed over the entire trip is 3.94 m/s

Step-by-step explanation:

As we know :
`speed=(distance)/(time)`

Let the distance of straight line from point to point be = d

Total distance covered = 2d

Time taken to cover the forward journey =
`(d)/(5.40)`

Time taken to cover the backward journey =
`(d)/(3.10)`

Total time for the journey = Time taken to cover the forward journey + Time taken to cover the backward journey =
`(d)/(5.40)+(d)/(3.10)`

Average speed =
`\frac{\text {total distance}}{\text {total time}}=(2d)/((d)/(5.40)+(d)/(3.10))=3.94m/s`

Thus average speed over the entire trip is 3.94 m/s