Physics acceleration question?

Question

A passenger bus travelling 28.0m/s to the right when the driver applies the brakes. Thebus stops in 5.00s. What is the acceleration (a->) of the bus as it comes to a stop? Show work please THANKS!

Answer 1

whats given?

Velocity intial= 28.0m/s

Velocity final = 0m/s ( it will stop at the end)

time= 5sec

from the unifrom accleration formula:

acceleration = (Velocity final - Velocity intial) / time

now subsitute:

acclereration =  ( 0m/s - 28.0m/s ) / 5 seconds

acclereration =  - 5.6 m/s^2

-ve acceleration means " Deceleration" to bring it to stop

Answer 2

a = dV/dt = -28/5 = -5.6 m/s²

The - is because the acceleration is in the direction opposite the velocity.