Motion Lab

1-D Toy Car
Goal:
Our goal is to determine the motion of a car moving along the horizontal, while taking into consideration its position, velocity and acceleration. By doing so, the physicists have the opportunity of understanding how an object tends to move and how it is affected by the surrounding factors.
Hypothesis:
First of all the car starts at a rest therefore we believe there will be some sort of acceleration. In this experiment, we have to take into consideration air resistance and friction which will cause a deceleration. This is why we believe that the car will slow down after a certain period of time, in other words, it will decelerate until it comes to a stop.
Materials:
Model car
Paper strip
Spark timer
Spoon
Meter stick
Tape
Procedure:
1. Place the model car at the beginning of the distance to cover, in front of an object so that the car can push on it.
2. Insert the paper strip in the extremity represented with a small arrow.
3. Once inside the spark timer, pull out the extra length of paper strip (approximately 15cm) from the other extremity and tape it on the car model.
4. Start the spark timer
5. When ready, one of the physicist triggers the car with a spoon
6. Turn off the spark timer
7. Take off the paper strip and keep it for data.
8. Record Data

Data/Results

Time(s)
0
0.1
0.2
0.3
0.4
0.5
0.6
0.7
0.8
Displacement(m)
0
0.052
0.106
0.161
0.2155
0.2685
0.3215
0.3725
0.423
Velocity(m/s)
0
0.52
0.54
0.55
0.545
0.53
0.53
0.51
0.505
Acceleration(m/s2)
0
5.2
0.2
0.1
-0.05
-0.15
0
-0.2
-0.05

0.9
1
1.1
1.2
1.3
1.4
1.5
1.6
1.7
1.8
0.472
0.5195
0.566
0.611
0.655
0.697
0.738
0.7775
0.8155
0.8525
0.49
0.475
0.465
0.45
0.44
0.42
0.41
0.395
0.38
0.37
-0.15
-0.15
-0.1
-0.15
-0.1
-0.2
-0.1
-0.15
-0.15
-0.1

1.9
0.8875
0.35
-0.2

total time= 1.9s total displacement= 0.8875m average velocity= 0.467m/s

Analysis (with calculations)

Position-time graph: (Graph is on page 6) Our position time graph shows the displacement of the car over time. The curve shows that the car is moving away from the initial position as it is always positive. However the curve is not straight since the displacement is not the same for every 0,1 second in motion. As time goes by, the displacement of the 0,1 second is shorter than that of the previous 0,1 second. This goes on until the car stops at 0,8875m from its initial position where the track ends.

Velocity-time graph: (Graph is on page 6) Our velocity time graph shows the velocity of the car over time. The initial velocity of the car is of 0 m/s since it starts at a rest. Once the car is triggered, we can notice an increase in velocity from 0s to 0,3s since it is now in motion. The velocity of the car until it stops is positive but decreasing because the change in displacement for every second is decreasing.

Acceleration-time graph: (Graph is on page 7) Our acceleration time graph shows the acceleration of the car over time. The peak at the beginning of the graph shows the acceleration of the car as it passes from a rest to in motion. When the curve crosses the x-axis it is the moment where the velocity has peaked and is now decreasing giving the car and the graph a negative acceleration. The rest of the graph shows fluctuations in acceleration all less than or equal to zero proving that the car is slowing down because of the deceleration.

Time: time is recorded on the strip of paper by the spark-timer. Every 6 markers are equal to 0.1 second since the spark-timer’s frequency is of 60Hz. To find the total time we group the markers by 6 and counted the number of groups. The result, 19 groups which means the car travelled for 1.9s before getting off the track.

Displacement: Displacement is recorded on the paper strip. The distance between every 6th markers is the displacement for that 0.1 second. Velocity: Velocity is determined