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To see that something is in motion you need a reference point. A reference point is just a still object that lets you see that the moving object moved.
You can tell that the car moved because it started on the left of the weird globe tree and ended at the right of it (seriously why is it a globe). Anyway this is called relative motion.
Next is the difference between distance and displacement. Distance is haw far you travelled while displacement if how far the end point is from the start. Displacement is always a straight line while distance can be curved or may turn. This is because in the real world you can't alwas go straight to your destination. There may be a mountain or a lake in the way. More commonly you are driving and have to follow roads.
Now we will talk about speed. Speed is the distance something has traveled in a unit of time. It could be measured in miles, yards, feet, or inches and seconds, minutes, and hours. Every country except for 'Merica is smart enough to use the metric system. So they use kilometers, meters, or centimeters. You find the speed by dividing the distance you by the speed. So the equation is S=d/t.
For example if you went 20 miles and it took you 5 minutes to find your speed you would divide the 20 miles by the 5 minutes and get 4 miles a minute. Usually people don't use minutes. People use kilometers per hour, meters per second, or miles an hour.
Next I will talk about instantaneous speed and average speed. Instantaneous speed is the speed at a certain point in time. So if you are going 15 miles per hour then that is your instantaneous speed, but if you stop at a stop sign then your instantaneous seed changes to 0 because at that instant you are stopped and are not moving.
In traffic you start and stop a lot. Here you can use average speed. For example if you go down a road with a lot of traffic and the road is 60 miles long. It takes you 3 hours to get through. Your average speed would be 20 miles an hour even though you were stopped a lot.
Next is Velocity. Many people think velocity is the same as speed and in a way it is but it has one key part that makes it different. Velocity has to do with direction. For example a car may be going 50 miles an hour North. Because you added the "North" it changes it to the car's velocity instead of its speed. Your need to know the speed and direction to state the velocity. For example if you are in a car your velocity may be 30 miles per hour North. Then if you turn left your velocity will change to 30 miles per hour West. Also if you slow down your velocity changes. So it might change to 10 miles per hour West.
Interesting facts:
Cheetahs run 112–120 km/h
The Peregrine falcon can dive at 389 km/h
This makes the Peregrine falcon the fastest animal in the world
Links:
Arsenal goal
2nd and 3rd arsenal goal
Reference point
Distance and displacement
Speed formula
Speed limit
Traffic
Velocity
Cheetah running/cheetah baby
