Answer:
The final velocity v is 21.74 m/s.
Step-by-step explanation:
Given:
[tex]\textrm{initial velocity} = u = 9\ m/s\\\textrm{acceleration} = a = 7\ m/s^{2}\\\textrm{distance} = s = 28\ m[/tex]
To find:
[tex]\textrm{final velocity} = v = ?[/tex]
Solution:
As we know the third equation of motion is represented as
[tex]v^{2} = u^{2} + 2\times a\times s\\[/tex]
Substituting the values u, a and s in the above equation we get
[tex]v^{2} = 9^{2} + 2\times 7\times 28\\ =81 + 392\\=473\\[/tex]
[tex]v =\±\sqrt{473} \\v =\sqrt{473} \ \textrm{as acceleration is positive v is also positive}\\v = 21.74\ m/s[/tex]
