Speed
The average speed of a moving object is the total distance travelled divided by the total time elasped. Remember, speed is a scalar quantity.
To calculate speed, we use the equation:
To calculate speed, we use the equation:
Velocity
The key difference between speed and velocity is that while speed is a scalar quantity, average velocity (Vav), is a vector quantity. It is the total displacement, change in position, divided by the total time it takes for this motion (displacement). Uniform [Constant] velocity is when the motion of an object is constant (the speed is in a straight line). Non-uniform velocity is when the motion of the object is not at a constant speed or in a straight line. When motion is non uniform, there is accelerated motion. Constant velocity- no accelerated motion.
Instantaneous velocity is used to find the velocity of an object and a specfic point in time. To find the instantaneous velocity, a tangent must be drawn at the the point EQUATION FOR VELOCITY
Acceleration
Acceleration (Aav) is the rate of change of an object's velocity (∆v) over the change in time (∆t). To find acceleration, we can use the following equation:
So when the velocity of an object changes at a uniform rate, this uniform change is also known as uniform or constant acceleration. One example of this would be when an object is in free fall. The acceleration that occurs when an object is in free fall is known as the acceleration due to gravity (g). The acceleration due to gravity of an object near the Earth's surface is 9.81m/s/s. In terms of an acceleration vs. time graph, the slope calculated from a velocity vs. time graph is the acceleration.
Position vs. Time, Velocity vs. Time and Acceleration vs. Time Graphs
Finding position, velocity and acceleration can be done from using any one of the p vs. t, v vs. t, or a vs. graphs. To get from a Postion to Velocity graph finding the slope of the position time graph will result in the velocity which can then be graphed. The same can be said going from a velocity time graph to acceleration. Going from acceleration time graph to a velocity time graph (finding velocity from an acceleration graph), finding the area of the graph will result in the velocity. Again, the same can be said when finding the position from a velocity time graph, simply find the area (depending on the shape of graph, different area formulas may have to be used).
Practice
Quizzes /Worksheets
1. http://www.sparknotes.com/testprep/books/sat2/physics/chapter5section7.rhtml (multiple choice)
2. https://0af9f02f-a-62cb3a1a-s-sites.googlegroups.com/site/mrtrasksphysics/physics-11/unit-2---kinematics-in-1d/Worksheet-4-dvstandvvstgraphs.pdf?attachauth=ANoY7coE298BNIblIoC7YNPdORYr71SjV-_Sd2i-mv887DjypwRaeUJwmLIJM-Tx0J7tYgORdieTii742lgXuAX6ciTyfilxRCwdf4KGakf67-1OZijYMrBF7BnfGQ8iwe5MEItxRE0H3_Z7Hb0UDRwq0LHmir-MwNa6VWzoG1Pv1Ou1BkjcmmDdo-zNPC_ijPQ0cJld7sykptMeifnnNc57Ljh802q1uceAhFJmV-PvCxge7LNiblU_EEysSte7IlKBU8LRpKBUeGHlQbxV9tVC76hq8TJG0McVI1oaNx843FfWAT1Gws8%3D&attredirects=0 (motion graph worksheet)
3.https://docs.google.com/viewer?a=v&pid=sites&srcid=ZGVmYXVsdGRvbWFpbnxtcnRyYXNrc3BoeXNpY3N8Z3g6MTlkMTVkODQ4ZThkNmI5(mini quiz1- motion graphs)
4. https://docs.google.com/viewer?a=v&pid=sites&srcid=ZGVmYXVsdGRvbWFpbnxtcnRyYXNrc3BoeXNpY3N8Z3g6MzU4NmQxYWQ1MjRhYjJhMg (mini quiz2- motion graphs)
5. http://www.stmary.ws/highschool/physics/home/marys_java/kinematics/kinematicsQ.html (multiple choice)
Simulations/ Videos
1. http://phet.colorado.edu/en/simulation/moving-man (understanding motion graphs)
2. http://graphs.mathwarehouse.com/distance-time-graph-activity.php (further your understanding of p vs. t graphs)
3. http://www.explorelearning.com/index.cfm?method=cResource.dspDetail&ResourceID=301 (gizmo- motion graphs)
4. http://www.bbc.co.uk/schools/gcsebitesize/science/add_ocr_gateway/forces/changingspeedact.shtml (further understanding of d vs t and v vs t graphs)
1. http://www.sparknotes.com/testprep/books/sat2/physics/chapter5section7.rhtml (multiple choice)
2. https://0af9f02f-a-62cb3a1a-s-sites.googlegroups.com/site/mrtrasksphysics/physics-11/unit-2---kinematics-in-1d/Worksheet-4-dvstandvvstgraphs.pdf?attachauth=ANoY7coE298BNIblIoC7YNPdORYr71SjV-_Sd2i-mv887DjypwRaeUJwmLIJM-Tx0J7tYgORdieTii742lgXuAX6ciTyfilxRCwdf4KGakf67-1OZijYMrBF7BnfGQ8iwe5MEItxRE0H3_Z7Hb0UDRwq0LHmir-MwNa6VWzoG1Pv1Ou1BkjcmmDdo-zNPC_ijPQ0cJld7sykptMeifnnNc57Ljh802q1uceAhFJmV-PvCxge7LNiblU_EEysSte7IlKBU8LRpKBUeGHlQbxV9tVC76hq8TJG0McVI1oaNx843FfWAT1Gws8%3D&attredirects=0 (motion graph worksheet)
3.https://docs.google.com/viewer?a=v&pid=sites&srcid=ZGVmYXVsdGRvbWFpbnxtcnRyYXNrc3BoeXNpY3N8Z3g6MTlkMTVkODQ4ZThkNmI5(mini quiz1- motion graphs)
4. https://docs.google.com/viewer?a=v&pid=sites&srcid=ZGVmYXVsdGRvbWFpbnxtcnRyYXNrc3BoeXNpY3N8Z3g6MzU4NmQxYWQ1MjRhYjJhMg (mini quiz2- motion graphs)
5. http://www.stmary.ws/highschool/physics/home/marys_java/kinematics/kinematicsQ.html (multiple choice)
Simulations/ Videos
1. http://phet.colorado.edu/en/simulation/moving-man (understanding motion graphs)
2. http://graphs.mathwarehouse.com/distance-time-graph-activity.php (further your understanding of p vs. t graphs)
3. http://www.explorelearning.com/index.cfm?method=cResource.dspDetail&ResourceID=301 (gizmo- motion graphs)
4. http://www.bbc.co.uk/schools/gcsebitesize/science/add_ocr_gateway/forces/changingspeedact.shtml (further understanding of d vs t and v vs t graphs)