Speed Flashcards
speed…
a measure of how fast an object is moving
distance…
the total movement of an object without any regard to direction
time…
time is change, or the interval over which change occurs
formula for speed?
speed = distance/time (for a section of a distance-time graph)
stationary…
Not moving- shown on a distance time graph by a horizontal line
constant speed…
Steady speed - the speed is not changing. The object travels the same distance each second
acceleration
Increasing speed over time.
deceleration…
Decreasing speed over time
what is a distance-time graph?
Distance-time graphs show how the distance travelled by a moving object changes with time and it shows an object’s journey through distance and time.
In a distance-time graph, the slope or gradient of the line is equal to the speed of the object. The steeper the line (and the greater the gradient) the faster the object is moving.
describe the journey of this distance time-graph:
Owais leaves his home at 4:00pm and travels 30km in 30 minutes. He then stops for fuel for 15 minutes. He then travels 20km in 15 minutes. He then stops at his friend’s house for 15 minutes. He then leaves and gets back to his house at exactly 6:15pm.
work out the speed of this question:
A race car travels 2km in 0.5 minutes.
2km = 2000m
0.5 minutes = 30 seconds
speed = distance/time
speed = 2000/30
speed = 66.6666666667m/s
speed = 66.7m/s (1 d.p)
average speed formula
average speed over a journey = total distance travelled/total time taken
