Motion
Change in the position of an object with time.
Is it wrong to say that you are moving at different speeds?
Your speed is dependent on your reference point so you are moving at different speeds depending on what point you are comparing yourself to.
Which line shows distance:

Red line
What is the formula for velocity from positions and times?
v = (final position - initial position)/(final time - initial time)
How do you determine if an object is accelerating or decelerating on a position time graph?
By looking at how the steepness changes in the curve over time.
Distance and Displacement
Distance: Total length traveled during a path.
Displacement: The difference and direction between the starting and ending point.
How can we determine if we are moving? What do we need to state?
You must know the reference point and measure how much you move away from or towards the reference point in a certain period of time.
Which line shows displacement?

Blue line
A comet is cruising through the Solar System at a speed of 50,000 kilometers per hour for 4 hours time. What is the total distance traveled by the comet during this time?
50,000 x 4 = 200,000 km
Sketch how forward deceleration would look on the PT graph.

Speed and Velocity
Speed: The amount of distance traveled per unit of time.
Velocity: The same as speed but with direction.
What is the difference between relative motion and absolute motion?
Relative motion: motion that happens with respect to a reference point (constant velocity)
Absolute motion: motion that is absolutely happening (change in speed or rotation)
What is the distance traveled?

7 m
If a speed skater on a straight track starts skating at a constant speed at meter 100 at 80 seconds and ends at that speed at meter 300 at 120 seconds, what was their velocity for that part of the race?
(300-100)/(120-80)= 200/40= 5 m/s
Sketch how backward aceleration would look on the PT graph.

Scalar and Vector quantities
Scalar: Quantities that just indicate magnitude.
Vector: Quantities with both magnitude and direction.
What are 2 ways in which you can measure how far you travel?
Distance and Displacement
What is the displacement?

5 m Southwest
Jessica jogs on a path that is 25 kilometers long to get to a park that is south of the jogging path. If it takes Jessica 2.5 hours, what is her velocity?
25/2.5= 10 km/hr
A ball rolls down a ramp for 15 seconds. If the initial velocity of the ball was 0.8 m/s and the final velocity was 7 m/s, what was the acceleration of the ball?
a = (7 - 0.8)/15 = 6.2/15 = 0.41 m/s2
Acceleration
Change in the velocity of an object with time.
If an object is moving backwards, how is it represented mathematically?
With a negative sign.
What is the displacement?

30 mi East or -30 mi
What is happening to the object when you see a horizontal line on a position time graph? What about a velocity-time graph?
Position time graph: The object is not moving.
Velocity time graph: The object is moving at a constant velocity.
A car going 50mph accelerates to pass a truck. Five seconds later the car is going 80mph. Calculate the acceleration of the car.
a = (80 - 50)/5 = 30/5 = 6 mi/h2