1.
In a mathematical model in the form of y=mx + b for a position-time graph, what does the following describe:
y-value
x-value
slope
y-intercept
2.
A runner's position is 40 m at time t = 0 s.
If he runs at a constant pace of 1.5 m/s, what will his position be at t = 45s?
Correct Answer
B. 107.5 meters
Explanation
The runner's initial position is given as 40 m at time t = 0 s. Since he runs at a constant pace of 1.5 m/s, we can calculate his position at t = 45 s by multiplying his velocity (1.5 m/s) by the time interval (45 s) and adding it to his initial position (40 m). Therefore, the runner's position at t = 45 s will be 1.5 m/s * 45 s + 40 m = 67.5 m + 40 m = 107.5 meters.
3.
A runner's position is 20 m at time t = 0 s.
If he runs at a constant pace of 0.5 m/s, what will his position be at t = 45s?
Correct Answer
C. 42.5 meters
Explanation
The runner's position at time t = 0 s is given as 20 m. Since the runner is running at a constant pace of 0.5 m/s, we can calculate his position at t = 45 s by multiplying the pace by the time. Therefore, the runner will have covered a distance of 0.5 m/s * 45 s = 22.5 m. Adding this distance to the initial position of 20 m, we get a final position of 20 m + 22.5 m = 42.5 m.
4.
Use the data below to answer the following question:
Is the velocity of the object constant? If so, what is the object's velocity?
Time (s) Position (m)
0.0 30
1.0 40
2.0 50
3.0 60
4.0 70
5.0 80
Correct Answer
C. Yes; + 10 m/sec
Explanation
The object's velocity is constant because the position increases by a consistent amount of 10 meters every second. This indicates that the object is moving at a steady pace without any acceleration or deceleration. The +10 m/sec indicates that the object is moving in the positive direction along the position axis.
5.
Use the data below to answer the following question:
What is the starting position of the object?
Time (s) Position (m)
0.0 30
1.0 40
2.0 50
3.0 60
4.0 70
5.0 80
Correct Answer
B. +30 meters
Explanation
The starting position of the object is +30 meters. This can be determined by looking at the position values at time 0.0 seconds, which is given as 30 meters.
6.
Use the data below to answer the following question:
Write an equation for the object's position over time.
Time (s) Position (m)
0.0 30
1.0 40
2.0 50
3.0 60
4.0 70
5.0 80
Correct Answer
D. X = (+10 m/sec) (t) + 30 m
Explanation
The equation X = (+10 m/sec) (t) + 30 m represents the object's position over time. The +10 m/sec indicates that the object's position is increasing by 10 meters per second. The (t) represents the time in seconds. The +30 m indicates that the object's initial position is 30 meters. Therefore, as time increases, the object's position increases by 10 meters per second.
7.
Use the data below to answer the following question:
Use your equation to solve for the object's position at time 15.0 s
Time (s) Position (m)
0.0 30
1.0 40
2.0 50
3.0 60
4.0 70
5.0 80
Correct Answer
B. +180 m
8.
Use the graph below to answer questions
#7: What interval had the greatest velocity?
Correct Answer
B. 5-7 sec
Explanation
The interval from 5-7 seconds had the greatest velocity. This can be determined by looking at the graph and observing that the slope of the line during this interval is steeper compared to the other intervals. A steeper slope indicates a higher velocity. Therefore, the 5-7 second interval had the greatest velocity.
9.
Use the graph below to answer questions
#8: What interval had the most negative velocity?
Correct Answer
D. 12-14
Explanation
The interval from 12-14 seconds had the most negative velocity. This can be determined by looking at the graph and observing that the slope of the line during this interval is the steepest and goes downwards, indicating a negative velocity.
10.
Use the graph below to answer questions
#9: Describe the motion of the vehicle at 10 seconds?
Correct Answer
C. The vehicle is at a constant velocity and not moving.
Explanation
At 10 seconds, the graph shows a horizontal line, indicating that the vehicle's position is not changing over time. This means that the vehicle is not moving. Additionally, since the line is horizontal, it indicates that the vehicle's velocity is constant (not changing) during this time period. Therefore, the correct answer is that the vehicle is at a constant velocity and not moving.
11.
Use the graph below to answer questions
#10: Describe the motion of the vehicle at 10 seconds?
Correct Answer
C. The vehicle is at a constant velocity and not moving.
Explanation
According to the graph, at 10 seconds, the position of the vehicle remains constant, indicating that it is not moving. Additionally, the slope of the graph is zero at this point, which means that the velocity is also constant. Therefore, the correct answer is that the vehicle is at a constant velocity and not moving.
12.
Use the graph below to answer questions
#11: Describe the motion of the vehicle at 2-5 seconds
Correct Answer
D. Velocity = -1 m/sec, traveling in the negative direction
Explanation
The graph shows that the velocity of the vehicle decreases from 1 m/sec to -1 m/sec between 2-5 seconds. Since the velocity is negative, it indicates that the vehicle is moving in the negative direction, opposite to the positive direction. Therefore, the correct answer is "Velocity = -1 m/sec, traveling in the negative direction."
13.
Is this graph possible? Can it describe the motion for one vehicle in a single trial? Choose the best answer below.
Correct Answer
A. No, a vehicle can't be in the same position at the same value.
Explanation
The answer is correct because it is not possible for a vehicle to be in the same position at the same time value. This would violate the basic principles of physics and the concept of motion. In a single trial, a vehicle can have different positions at different time values, but it cannot occupy the same position at the same time.
14.
Use the following for questions
What happens when the lines above the cross?
Correct Answer
A. CMV1 and CMV2 crash
15.
Use the following for questions
Which CMV has moved more position overall from 0-15 seconds?
Correct Answer
B. CMV2
Explanation
CMV2 has moved more positions overall from 0-15 seconds compared to CMV1.
16.
Use the following for questions
Which answer best supports your response in #14
Correct Answer
B. CMV2 has changed more position over this time period than CMV1
Explanation
The answer states that CMV2 has changed more position over this time period than CMV1. This implies that CMV2 has traveled a greater distance or has experienced a greater change in position compared to CMV1.
17.
Imagine x-axis is time (sec) and y-axis is position (m)
What was the velocity from 0-2 seconds?
Correct Answer
0m/sec
0 m/sec
0 m /sec
0 m/ sec
0m/ sec
Explanation
The velocity from 0-2 seconds is 0m/sec. This means that there is no change in position during this time interval, indicating that the object is not moving. The various options provided are just different ways of representing the same value of velocity, which is 0m/sec.
18.
Imagine x-axis is time (sec) and y-axis is position (m)
What was the velocity from 9-10 seconds?
Correct Answer
-3m/sec
-3 m/sec
-3 m /sec
-3 m/ sec
-3m/ sec
Explanation
The correct answer is -3m/sec. The negative sign indicates that the velocity is in the opposite direction of the positive x-axis. The unit "m/sec" represents the rate of change of position with respect to time. Therefore, the velocity from 9-10 seconds is -3 meters per second.
19.
Imagine x-axis is time (sec) and y-axis is position (m)
What was the overall change of position for this object from time 0 to time 11?
Correct Answer
-1 m
-1 meter
-1m
-1meter
Explanation
The overall change of position for the object from time 0 to time 11 is -1 meter. This means that the object moved 1 meter in the negative direction along the y-axis during this time interval.