Respuesta :

Let us first calculate the speed of the arrow going upwards.
Initial velocity = 15 m/s
Final velocity = 0 m/s
Let us assume the time taken = t
Then
0 = 15 - 9.8t
9.8t = 15
t = 15/9.8
  = 1.53 second
Now
Let us calculate the speed of the arrow going downwards
Initial speed = 0 m/s
Final speed = 8 m/s
Then
8 = 9.8t
t = 8/9.8
  = 0.816 second
Then
Total time = 1.53 + 0.816
                 = 2.346 second
I hope the answer helps you.

Answer:

t = 2.34 s

Explanation:

As we know that

initial velocity is 15 m/s upwards

final velocity is 8 m/s downwards

acceleration is due to gravity which is given as g = 9.8 m/s/s in downwards direction

now we can find the time to change the velocity using equation of kinematics

[tex]v_f - v_i = at[/tex]

here we need to plug in all data

[tex](-8) - 15 = (-9.81) t[/tex]

[tex]t = \frac{-23}{-9.81}[/tex]

[tex]t = 2.34 s[/tex]

so it will take t = 2.34 s