Another Science problem?

Question

As a bus approaches a turn it goes from 30 m/s to 5 m/s in a space of 5 seconds. What was its acceleration?

MORE! MORE MORE! I NEED MORE ANSWERS PLEASE! AND MORE SIMPLER TO UNDERSTAND! HELP ME!

Answer 1

It accelerated 25 m/s, in the direction opposite to the velocity of the bus, in 5 s, so assuming it was a constant acceleration, the result is:

a = 25 m/s / 5 s = 5 m/s^2

(In the stated direction of course)

Edit: Ok, I'll try to clarify at your request.

Accelerating in the direction opposite to a movement is the same as deaccelerating that movement, do you see it? You could speak of "negative acceleration" and people would understand, but strictly speaking, in physics, accelaration is incomplete if you don't specify a direction (are you accelerating upwards, to the left or what?) so there is no need to use negative numbers -- just specify the right direction. In this case, it is the direction opposite to the movement of the bus.

s^2 means "s squared", which is the same as s times s.

An accelaration of 5 m/s^2 means that, every second, the speed changes 5 m/s. Maybe it would be clearer if you rewrote it as 5 (m/s) / s (or 5 m/s per second). So, in 5 s, it would change 25 m/s, as in your question, because 5 s times 5 m/s^2 is equal to 25 m/s. To find that number I did the inverse: I divided 25 m/s by 5 s.

Observe that I operate on the units too, not only on the numbers, and the resulting unit makes sense. For example when dividing m/s (a speed) by s (a period of time) the result is m/s^2 (an accelaration). If the resulting unit is wrong then you are making a mistake (probably using the wrong formula).

If you have any remaining doubts please let us know what they are.

Answer 2

Use the formula

Vf = Vo + at

where

Vf = Final Velocity
Vo = Initial Velocity
a = acceleration
t = time

if you solve for "a" you get

a = (Vf -Vo)/t

substituting known quantities

a = (5 - 30)/5 = -5

so you have a negative acceleration of 5 m/s^2

I hope this is clear enough for you

:-)

Answer 3

acceleration= change in velocity/ change in time
a= 5-30/5=-25/5 = -5 m/s^2

Answer 4

how does somthing accelerate when its reducing its speed

Answer 5

you mean deceleration