A ball is thrown upward. The total time the ball remains in the air is 14 s. a) With what speed was the ball thrown upward? b) What is the maximum height reached by the ball?

a) Vi = 137.2 m/s

b) h = 960.4 m

Explanation:

a)

In order to find the initial speed we will use first equation of motion:

Vf = Vi + gt

where,

Vf = Final velocity = 0 m/s (since ball stops at highest point)

Vi = Initial Velocity = ?

g = - 9.8 m/s² (negative sign for upward moyion)

t = time interval = 14 s

Therefore,

0 m/s = Vi + (-9.8 m/s²)(14 s)

Vi = 137.2 m/s

b)

Now, we use second equation of motion to find height (h):

h = Vi t + (1/2)gt²

h = (137.2 m/s)(14 s) + (1/2)(-9.8 m/s²)(14 s)²

h = 1920.8 m - 960.4 m

h = 960.4 m

nah.   i'm just sleepy.

the skeletons of most mammals reach a certain size and then stop growing. however, many animals, including some mammals, keep growing throughout their lives. kangaroos, for example, just keep growing and growing until they die. also, the longer an animal lives the greater the chance it might catch some deadly disease.