Question

a scooterist moves with uniform acceleration of 2m/s for 5 seconds .find the final velocity if the final velocity if his present velocity is 18km/h?

Answer 1

u = 18 km/h = 5 m/s
a = 2 m/s²
t = 5 sec

From 1st equation,
v = u + at
   = 5 +2×5 
   = 15 m/s

Answer 2

Final velocity of the scooter is v = 15 m/s

Given:

Present velocity = 18km/hr

Uniform acceleration = 2m/s

Solution:

The scooter is moving with uniform acceleration it means the rate of acceleration changes with respective time interval. We know that the total change in velocity in a time is acceleration.

$a=\frac{v-u}{t}$

Where the final and initial velocities are denoted as ‘’v’’ and ‘’u’’ and the time taken is ‘’t’’

Given in the question, rate of acceleration $a=2 m / s^{2}$

Time taken t = 5 s.

Initial the scooter is travelling with velocity u =18 km/ h

Converting km /h to m/s, multiply by $\frac{5}{18}$ we get  

u = 5 m/s.

Substituting the values in the formula of acceleration

$2=\frac{v-5}{5}$

So the final velocity of the scooter is v = 15 m/s.