a train Going towards the South
direction with
an average speed of
50 km/h will have a velocity of
50 km/h, north. An object Going straight
in a particular direction is
considered to have velocity.
Answers
Explanation:
everyday conversation, to accelerate means to speed up. The accelerator in a car can in fact cause it to speed up. The greater the acceleration, the greater the change in velocity over a given time. The formal definition of acceleration is consistent with these notions, but more inclusive.
AVERAGE ACCELERATION
Average Acceleration is the rate at which velocity changes,
\displaystyle \bar{a}=\frac{\Delta v}{\Delta t}=\frac{{v}_{f}-{v}_{0}}{{t}_{f}-{t}_{0}}
a
¯
=
Δt
Δv
=
t
f
−t
0
v
f
−v
0
where \displaystyle \bar{a}
a
¯
is average acceleration, v is velocity, and t is time. (The bar over the a means average acceleration.)
Because acceleration is velocity in m/s divided by time in s, the SI units for acceleration are m/s2, meters per second squared or meters per second per second, which literally means by how many meters per second the velocity changes every second.
Recall that velocity is a vector—it has both magnitude and direction. This means that a change in velocity can be a change in magnitude (or speed), but it can also be a change in direction. For example, if a car turns a corner at constant speed, it is accelerating because its direction is changing. The quicker you turn, the greater the acceleration. So there is an acceleration when velocity changes either in magnitude (an increase or decrease in speed) or in direction, or both.