Question

V2=u2+2as v 2 = u 2 + 2 a s Where v v is the final velocity (in m/s), u u is the initial velocity (in m/s), a a is the acceleration (in m/s²) and s s is the distance (in meters). Find v v when u u is 9 m/s, a a is 7 m/s², and s s is 28 meters.

Answer 1

Final velocity, v = 21.75 m/s

Explanation:

Given that the relation between final velocity, initial velocity, acceleration and distance traveled is expressed as:

`v^2=u^2+2as`

Also, given that:

Initial velocity, u = 9 m/s

Acceleration, a = 7 m/
`s^2`

Distance, s = 28 m

To find:

Final velocity, v = ?

Solution:

The given relation between v, u, a and s is:

`v^2=u^2+2as`

We have the values of initial velocity, acceleration and distance traveled in the question statement. We just need to put all these values to find the value of final velocity.

Let us put all the values in the given equation and try to find final velocity, v:

`v^2=9^2+2* 7 * 28\\\Rightarrow v^2=81+14 * 28\\\Rightarrow v^2=81+392\\\Rightarrow v^2=473\\\Rightarrow v=√(473)\\\Rightarrow v=21.75\ m/s`

So, the answer is:

final velocity, v = 21.75 m/s