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Velocity
Velocity
(v)
is
displacement
rate
of
change
with
respect
to
time.
.
In
general,
velocity
is equal
to speed, except with additional
information of
direction.
For
instance,
a
car
travels
80km/h
from
A
to
B,
means
that
it
goes
with
speed
80km/h
from
A
to
B.
To
indicate
velocity
of
the
car,
a
direction needs to be added. E.g. a car travels 80km/h, east towards B
from
A.
-
Acceleration
Acceleration
is
velocity
rate
of
change.
An
object
is
stated
to
accelerate
if
its
velocity
changes.
These
changes
can
be
in
an
increasing or
decreasing
manner depends whether the acceleration is positive or negative, in
which a
positive
acceleration
implies
acceleration
and
negative
acceleration
refers
to
deceleration.
For
example,
a
car
at
rest
accelerates
to
30m/s
within
3
seconds. What is the magnitude of this acceleration?
Answer:
u
=
0
m/s Å at rest
v
=
30 m/s Å after acceleration
t
=
3s Å time that it takes for a car to accelerates
a=? Å acceleration
v
=
u
+
a
x
t
30m/s = 0 m/s + a x 3s
30m/s = a x 3s
a
=
10m/s²
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