The greatest speed for each racer is represented by the longest
distance between two dots. Since each dot is 0.1 seconds apart we can find
the instantaneous speed.
The same applies for the lowest speed. In this case we measure the shortest
distance between two dots and divide by the time (0.1s)
The average speed of each racer is given by dividing the total distance
travelled by the time taken. Since all three dragsters covered the 18m course
the average speed can be calculated by dividing 18m by the time taken The
time taken can be calculated by counting the dots which represent 0.1s each.
To work out the time elapsed between the first and last dots of racer "B"
count the number of dots (which represent 0.1 seconds) and multiply this
number by 0.1.
Zero acceleration is achieved when the object is stationary or travelling
at constant speed. If the sequential dots are evenly spaced apart then the
dragster is travelling at constant speed and therefore with zero acceleration.
The acceleration formula is given as
(change in speed)/time taken
We first have to find the speed over the first 0.1s of travel. Since dragster
"C" covers 1m in 0.1 seconds we can say that its speed is 10m/s
(1m/0.1s) .
Next we calculate the speed over the next 0.1s interval here the dragster
travelled a further 2m in 0.1seconds. We can therefore calculate the speed
over this time period as 20m/s (2m/0.1s).
To find the acceleration should now be easy knowing that at the end of 0.1
seconds the speed was 10m/s and at the end of 0.2 seconds the speed had
increased to 20m/s.
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The car travels 70m in 4 seconds. Its speed at the 70m mark
is 17.5m/s (70m/4s).
Acceleration is the change in speed divided by the time taken. Since the
initial speed is 0 (stationary start) the change in speed is given by subtracting
the initial speed from the final speed. Since the time taken for this change
is speed to occur is known (4 seconds) we can calculate the acceleration
over the initial 70m.
During the last second of travel the vehicle covered a distance of 3m in 1 second. The speed should be easy to calculate.
In order to work out if the driver was accelerating or decelerating at the moment of impact the speed during the second last time interval should be calculated and used to work out the acceleration or deceleration of the vehicle.
The average speed of the vehicle over its entire journey is calculated by taking the total distance travelled and dividing by the total time taken.
Distance, speed and acceleration exercises 

Three drag racers raced each other. Each racer was fitted with a special device that made a mark on the ground 10 times every second. Answer the following questions. What is the greatest speed
for each racer? What is the lowest speed of each racer? What is the average speed of each racer? How many seconds have elapsed between the first and last dots of racer "B" Over what distance is the acceleration of racer "C" zero? What is the acceleration of racer "C" over the first 3m of the race? Clues. See your teacher for detailed solutions. 



A car drips oil at the rate of one drop per second. It starts on the left side of the street and speeds towards the right where it crashes into a brick wall. Above is the pattern made by the vehicle on the straight road. Each square represents 10m. a) What is the acceleration of the vehicle over the first 70m? b) What is the speed of the vehicle upon impact at the end? c) Was the driver accelerating or decelerating at the moment of impact? d) What was the average speed of the vehicle?
Clues. If you are experiencing difficulties seek assistance from your teacher. 
