DISTANCEDISPLACEMENT POSITION GRAPH VS TIME Physics Mr Villa

DISTANCE/DISPLACEMENT POSITION GRAPH VS. TIME Physics Mr. Villa

From last time………… Distance is……. . Displacement is……. Speed is……. . Velocity is……. .

From last time………. A physics teacher walks 4 meters East, 2 meters South, 4 meters West, and finally 2 meters North. W E What is the total distance? 12 meters What is the total displacement? 0 meters. Started and finished in the same

From last time………. A physics teacher walks 4 meters East, 2 meters South, 4 meters West, and finally 2 meters North. All this, done in 24 seconds. W E What is the avg. speed? 0. 50 m/s What is the avg. velocity? 0 m/s. 0 displacement/24 seconds =0

Graphing Linear Motion There are three different types of linear motion graphs that we will by analyzing. �Displacement vs. Time Describes how an objects position is changing over time �Velocity vs. Time Describes how an objects velocity is changing over time

Position-Time Graphs Show an object’s position as a function of time. x-axis: time y-axis: position

Position-Time Graphs Imagine a ball rolling along a table, illuminated by a strobe light every second. 0 s 1 s 2 s 3 s 4 s 5 s 6 s 7 s 8 s 9 s 10 s You can plot the ball’s position as a function of time.

Position-Time Graphs 10 9 position (cm) 8 7 6 5 4 3 2 1 1 2 3 4 5 6 7 8 9 10 time (s)

Displacement vs. Time The slope of the line at any given point will equal the velocity of the object at that point. � Straight flat line → no movement �Straight non-flat line → constant velocity (no acceleration) �Curved line → accelerating

Example 1 The displacement-time graph for a tennis ball which is thrown vertically up in the air from a player’s hand then falls to the ground.

Example 2 A bus travels along a straight road for 600 m. It travels at a constant velocity for the whole journey, which takes 90 s. Sketch the displacement-time graph. What was the velocity of the bus?

Examples Draw a displacement vs. time graph for the following: �A tennis ball bouncing up and down

Examples Draw a displacement vs. time graph for the following: �A track star running the 400 m

Examples Draw a displacement vs. time graph for the following: �A baseball thrown up and then caught again

Examples Draw a displacement vs. time graph for the following: �A baseball thrown up and then allowed to hit the ground

Velocity vs. Time The slope of the line at any given point equals the objects acceleration at that point. �Straight flat line → no acceleration (constant speed) �Straight non-flat line → constant acceleration �Curved line → increasing/decreasing acceleration The area under the line equals the displacement of the object up to that point.

From last time……. .