Question

Abby throws a ball straight up and times it. She sees that the ball goes by the top of a flagpole after 0.50 s and reaches the level of the top of the pole after a total elapsed time of 4.1 s. What was the speed of the ball at as it passed the top of the flagpole? Neglect air resistance.

Answer 1

`v_f = 35.3 m/s`

Step-by-step explanation:

It took 4.1 s to reach the top point of its path

so after t = 4.1 s the final velocity of the ball will become zero

so we will have

`v_f = v_i + at`

`0 = v_i - (9.81)(4.1)`

`v_i = 40.22 m/s`

Now we have to find the speed of ball after 0.5 s when it will reach the top of the pole

so it is given as

`v_f - v_i = at`

`v_f = 40.22 - (9.81)(0.5)`

`v_f = 35.3 m/s`

Answer 2

Speed is a measure of how quickly an object moves from one place to another. It is equal to the distance traveled divided by the time. It is possible to find any of these three values using the other two.

The solution would be like this for this specific problem, please see attached image.

The speed of the ball as it passed the top of the flagpole is 17.6 m/s.