Transcript The Kinematic Equations

The Kinematic Equations
Kinematics
Describes motion without regard to
what causes it.
Uses equations to represent the motion
of an object in terms of acceleration
(a), velocity (v), displacement (d) and
time (t).
Equations
vf = vi + at
d = (vf + vi)t
2
d = vit + ½at2
vf2 = vi2 + 2ad
If a car’s initial velocity is +25 m/s, and
it accelerated at a rate of +7.5 m/s2 over
a period of 8.0 seconds what is the car’s
final velocity?
vf = 85 m/s
vf = vi + at
If a kicker boots the ball at a velocity of
+45 m/s and it is aided by a gust of
wind to accelerate at +2.5 m/s2 and it
stays in the air for 3.5 seconds. How
far will the ball travel?
d = +170 m
d = vit + ½at2
A boy sledding down a hill has an initial
speed of +12m/s. He continues to
speed up and reaches a final velocity of
+18m/s after traveling for 12 seconds.
What distance does the boy travel.
d = +180 m
d = (vf + vi)t
2
Mr. Billante is notorious for his road rage.
After being cut off he accelerates at a rate of
+12.3 m/s2 for +455 m. As he approaches
the man who cut him off his final velocity is a
ludicrous +125 m/s. What was his initial
velocity?
vi = +66.6 m/s
vf2 = vi2 + 2ad
Free Fall
An object is in Free Fall if gravity is the
only force acting on an object.
(Assume no Air Resistance)
g = acceleration due to gravity on a
particular planet
g = - 9.8 m/s2