Speed, distance, time
Speed, Distance and Time
1.
A car travels 100m in 5s. What is its average speed? 20m/s
2.
A car is travelling at 30m/s how far does it travel in 60 seconds? 180m
3.
What does a horizontal line on a distance time graph represent? A stationary
object
4.
What does the gradient of a distance time graph represent? Speed
5.
Add the units to the distance time graph over the page. m and s
6.
What was the speed of the person between 10s and 50s? 3m/s
7.
Over which time period does the person go fastest? 80s-120s
8.
What does a horizontal line on a speed time graph represent? Constant speed
9.
What does the gradient of a speed time graph represent? Acceleration
10. Add the units to the speed time graph over the page. m/s and s
11. What are the units of acceleration? m/s2
12. How fast was the car accelerating between 0s and 40s? 0.5 m/s2
13. How fast did the car decelerate before coming to a complete stop? -1.5 m/s2
14. How far did the car travel in this time? 300m
15. How far did the car travel when travelling at 30m/s? 1200m OR 1.2km
Distance(____)
Distance Vs time
How
far Bob runs.
300
280
260
240
220
200
180
160
140
120
100
80
60
40
20
0
0
20
40
60
80
100
120
140
Time(___)
Speed Vs Time
How fast
a car is travelling.
35
30
Speed (____)
25
20
15
10
5
0
0
20
40
60
80
100
Time (____)
120
140
160
180
200
A child ran out in front of a car causing the driver to make an
emergency stop. The graph shows how the speed of the car
changed from the moment the driver saw the child.
(i) What was the driver’s reaction time?
(1 mark)
0.7 seconds (accept 1 second)
(ii) Describe the motion of the car during the first 0.5 seconds.
(1 mark)
Constant speed
(iii) How long did it take the car to stop once the brakes were applied?
(1 mark)
3.3 seconds (accept 3 seconds if answer for q1 was 1 second)
(iv) The drug cannabis makes the reactions of a person slower.
Explain how the stopping distance of the car would change if the
driver had been smoking cannabis.
(1) The reaction time of the driver would have been longer so the time
between seeing the child and applying the brakes would have been
greater.
(2) The braking distance would have been the same.
(3) The overall stopping distance would have been longer.