# Acceleration and speed

```6.3 Acceleration and speed-time graphs
1.
The speed-time graphs shows the journey made by a bicycle. Answer the following
the questions.
(a)
What happened to the bicycle between 40 and 50 seconds?
It shows that the bicycle is going down.
(b)
How many times during the journey did the bicycle move at constant speed?
2 times
(c)
For how long was the bicycle stationary?
5 seconds
(d)
What happened to the bicycle at 15 seconds?
The speed quickly became 0.
(e)
What was the speed of the bicycle after 10 seconds
the bicycle speed went down
(f)
For how long the bicycle was going at a speed of 8 m/s?
10 seconds
2.
The speed-time graph shows the journey made by a car.
The speed-time graph shows the journey made by a car
How far did the car travel in total?
(a)
90kph
(b)
How long was the car driving at its fastest?
0900
(c)
Between which times did the car accelerates fastest?
0909-0915
(d)
How long did the car take to reach 60 km/h?
(e)
10
At what time did the car start to slow down?
0916
(f)
What was the greatest speed reached by the car?
90kph
3
The speed-time graph shows the journey made by a toy vehicle.
(a)
How far did the vehicle travel in total?
1.5 m/s
(b)
Calculate the deceleration of the vehicle until it stopped.
-3
(c)
What was the acceleration of the toy vehicle at the very start of its journey?
(0,0) (0.5,1)
x2-y2, x1-y1
= -1/-0.5
=2
(d)
How long did it take the vehicle to reach a speed of 1 m/s?
1 second
(e)
For how long the vehicle was traveling at 1.5 m/s?
4.5 secs
(f)
Calculate the acceleration between 1 and 2 seconds.
(1,1) (2,1.5)
x2-y2,x1,x2
4
The speed-time graph shows the journey made by a car.
(a)
Calculate the acceleration at A, B, C and D on the graph.
(b)
Calculate distance travelled for the whole journey on the graph.
6.4 Presenting data from racing
1
.
The results of the investigation are shown in the table below.
Time
(days)
Rise in temperature
(0C)
0
0.0
1
0.2
2
2.0
3
4.0
4
5.0
5
5.4
6
5.6
7
5.6
Use the results to complete the line graph by:
(i)
completing the scale on the y-axis;
(ii)
adding a label to the y-axis;
(iii)
plotting the graph.
2
.
The table below shows the production of alcohol for use as an alternative fuel from
1998 to 2008.
Year
Alcohol production
(megalitres)
1998
4000
2000
6500
2002
11000
2004
12000
2006
13500
2008
17500
On the grid below, complete a line graph by:
(I) labelling the vertical axis
(ii)
adding an appropriate scale to the horizontal axis;
(iii)
plotting the graph.
```