Answer:
The instantaneous velocity after eight seconds is 9 m/s
Explanation:
Given as :
The ball shot upward with velocity of 15 m/s
The height of the ball after t sec is given as h(t) =
Now, The instantaneous velocity after 8 sec =
![(\partial h(t))/(\partial t)](https://img.qammunity.org/2020/formulas/mathematics/middle-school/owqskxhdz176m0hkri28q7yy7dpi27v08w.png)
Or, The instantaneous velocity =
or, The instantaneous velocity =
![5 + (1)/(4)* 2 t](https://img.qammunity.org/2020/formulas/mathematics/middle-school/qpu7k512r85n9p7d3pqv4s2tnafz7r9p33.png)
Now at t = 8 sec
The instantaneous velocity = 5 + 4 = 9 m/s
Hence The instantaneous velocity of ball at t = 8 sec , is 9 m/s Answer