Question

X (km)

1.8
1.6
1.4
1.2
1
0.8
0.6
0.4
0.2
0
Position vs. Time
0 5 10
15 20 25 30
t(s)
a. What is the distance traveled by the car between 1 and 9 seconds? (2 points)
b. What is the average speed of the car between 1 and 9 seconds? (Answer in
km/s.) (2 points)

Answer 1

The distance traveled by the car between 1 and 9 seconds is 0.8 km.

The average speed of the car between 1 and 9 seconds is 0.1 km/sec

A.)

From the graph :

Reading on the y-axis(distance) when the x-axis (time) value is 9 seconds is 1 km.

Reading on y-axis when x-axis(time) value is 1 second is 0.2 km

Distance traveled between 1 and 9 seconds:

• 1 km - 0.2km = 0.8 km

Hence, the distance traveled by the car between 1 and 9 seconds is 0.8 km.

B.)

The average speed of the car can be calculated using the formula;

• distance / Time

Distance traveled between 1 and 9 seconds = 0.8km

Time taken to travel = (9 - 1) = 8 seconds

Now we have;

Average speed = 0.8/8 = 0.1 km/sec

Hence, the average speed is 0.1 km/sec