Motion

05.05 |

Motion Definition

Ø Motion is a change of position or displacement of an object within a certain time interval.

Ø Motion is relative because it depending on its point of reference.

Ø Point reference is an object or location which is considered fixed (at rest) and used to compare the initial and final position.

Type of Motion

Ø Type of motion consist of : appearance motion and actually motion.

Ø Appearance motion is motionless environment toward move environment.

ü Example : moving the sun every day

Ø Actually motion is move environment toward motionless environment.

ü Example : we see car moving

Velocity

Ø Velocity is the change position within a time interval.

Ø Velocity has two components : magnitude and direction.

Ø Velocity is the speed with is direction.

S= V.T

T = S

V = S

Based on velocity, motion consist of :

V = S

Constant motion :

V = S .S

S.T

Average motion :

Speed

Ø Speed is the magnitude or absolute value. If the speed continuously changes, the appropriate way to express the speed is by the average speed.

Acceleration

Acceleration is the change of velocity with respect to time.

Acceleration magnitude is determined by two things, magnitude of velocity change an time interval of the change.

Acceleration consist of positive acceleration and negative acceleration.

Positive acceleration If is in the same direction as the direction of velocity.

Negative acceleration Direction of acceleration opposite to the direction of velocity will cause the velocity to decrease.

A = V₁ – V₀

T₀

Formula of acceleration is

Straight Motion

v Straight motion is movement of an object which its track is straight. Straight consist two parts, that is ;

ü Uniform straight motion is straight motion at constant speed.

Example : For this motion are battery powered toy car.

ü Uniformly accelerated straight motion of the acceleration is kept constant.

Example : For this motion are the motion of free falling.

Straight Motion Graphics

Example : over line indicate ability the first runner go thorough distance 40 meter during 10 second. The first runner run with velocity 4m/s. underline indicate ability the second runner moving with velocity changeable. During 10 first second velocity 2m/s; 10 second second break, its meaning velocity 0m/s; and 10 last second velocity 4m/s.

Distance (m)

120