Question

a body starts from rest and moves with a uniform acceleration of 4m/s2 until it travels a distance of 800m2. find the final velocity​

Answer 1

Let’s review the 4 basic kinematic equations of motion for constant acceleration (this is a lesson – suggest you commit these to memory):

s = ut + ½ at^2 …. (1)

v^2 = u^2 + 2as …. (2)

v = u + at …. (3)

s = (u + v)t/2 …. (4)

where s is distance, u is initial velocity, v is final velocity, a is acceleration and t is time.

In this case, we have u = 0, a = 4m/s^2 and s = 800m. We want to find v, so we use equation (2): v^2 = u^2 + 2as

v^2 = 0 + 2(4)(800) = 6400

so v = √6400 = 80m/s

The final velocity is 80m/s

Answer 2

Answer:

v°=0

a=4m/s

x=800m2. x=20√2

x=v°+at

t=x-v°\a

=20√2-0/4

=5√2sec

v=v°+1/2at

=0+1/2*4*5√2

=10√2m/s