Click here to load reader
Upload
felna00
View
478
Download
2
Embed Size (px)
Citation preview
RECTILINEAR
MOTION
MOTION
is the continuous change in
the position or location of an
object
TYPES OF MOTION
1. Curvilinear Motion
2. Rotational Motion
3. Vibratory Motion
4. Rectilinear Motion
Rectilinear Motion
is motion along a straight line
QUANTITIES OF MOTIONSpeed
a scalar quantity which is the ratio of
distance,d over elapsed time, t
units: m/s , cm/s , ft/s
Velocity, v
a vector quantity which is the ratio
of displacement,s over elapsed time, t
a speed with direction
units: m/s , cm/s , ft/s
Acceleration, a
a vector quantity which is the
measure of the change of velocity per
unit time
units: m/s2 , cm/s2, ft/s2
KINDS OF RECTILINEAR MOTION
1. Constant Motion
*or constant velocity (no acceleration)
*object traverses the same
displacement per unit time interval
2. Uniformly Accelerated Motion
*constant acceleration
*the object is moving with constant
acceleration
3. Variably Accelerated Motion
*acceleration is not constant
EQUATIONS FOR UNIFORMLY
ACCELERATED MOTION
EXERCISES
1. During a time interval of 5 hours, a
car travels toward the north a
distance of 350km. Find the average
velocity of the car.
2. The velocity of a train changes from
30km/h to 60km/h in 11 seconds.
Find its acceleration in m/s2.
3. Starting from rest, a truck acquires a
velocity of 20km/h during a time of 15
seconds. What is its acceleration in
m/s2?
4. The brakes of an automobile travelling
with a velocity of 20m/s are suddenly
applied. If the automobile comes to a
stop after 5 seconds, what is its
acceleration?
5. A bicycle starting from rest is
accelerated 5m/s2. How far will it
travel after 10 seconds?
6. A train changes its velocity from 30m/s
to 80m/s while travelling a distance of
140m. Find its acceleration. Find the
time it needs to change in velocity.
FREE - FALL
Motion of a Free-Falling Objects
is a special case of uniformly
accelerated rectilinear motion
g – the acceleration due to gravity or
gravitational acceleration
* 9.8 m/s2
*980 cm/s2
*32 ft/s2
EXERCISES
1. A ball is dropped from rest at a
height of 50 m above the ground.
What is the speed just before it hits
the ground? How long does it take to
reach the ground?
2. A stone is thrown vertically up. It
reaches a maximum height of 19.6
m. What is its initial velocity? After
how many seconds will it return to
the ground?
3. A ball is thrown vertically up and
returns to the ground after 6
seconds. With what velocity was it
thrown? How high did the ball go?