Forces and Motion Flashcards
What is speed?
Speed is the measure of how far you travel in a set amount of time.
What is the formula for speed, distance, and time?
(average) Speed = Distance (traveled) / Time (taken)
SIDOT = Speed Is Distance Over Time
What are the common units for speed?
metres per second – m/s
miles per hour – mph or miles/h
kilometres per hour – km/h
What do distance-time graphs do?
Distance-time graphs show the distance travelled by an object over time.
On a distance-time graph, what does the slope of the line (gradient) show?
It shows the speed at which the subject is moving.
The steeper the line, the faster the subject moves.
On a distance-time graph, what does a flat line represent?
it shows that the subject is stationary and the movement has stopped.
On a distance-time graph, what does a downhill line represent?
it shows that the subject is moving back to (returning) its starting point.
On a distance-time graph, what does a curve represent?
It shows the change of speed of a subject.
On a distance-time graph, what does a steepening curve represent?
It shows that the subject is increasing its speed (speeding up/accelerating).
On a distance-time graph, what does a curve that is leveling off (from a curve to a straight line) represent?
It shows that the subject is decreasing its speed (slowing down/decelerating)
What is relative motion?
Relative motion is used for when you want to know the speed of something when you, too, are in motion.
How do you calculate the relative motion of two objects that are moving in opposite directions on the same straight line?
You add their speeds together to calculate their relative motion.
How do you calculate the relative motion of two objects that are moving in the same direction on the same straight line?
You subtract their speeds to calculate their relative motion.
What is a force?
A force is a push or pull that occurs when two subjects interact with one another.
They cannot be seen, but the effects of a force can be visible.
What are forces measured in?
Newtons (N)
