Exploring acceleration through vectors
Initial Publication Date: September 2, 2008
Summary
The direction of accelerations and velocities is a hard concept to understand. This activity is designed to make the students look at it in at least two different ways. First the students think about a written situation and determine what direction of acceleration would be needed to get the given result then represent that acceleration graphically using vectors. Then in part two they are given the graphical representation and asked to write descriptions of the cars motion. The drawings and descriptions help to get different types of learners involved. Afterwards, the students can show their understanding either by turning the worksheet in, sharing their descriptions, or trying their solutions out on small cars.
CollapseLearning Goals
The goal of this activity is to get students to think about what is happening when velocity and acceleration vectors point in different directions. The pictures, sentences, and cars are used to allow the students to picture each situation in different ways.
Context for Use
oThis activity fits right after we define position, velocity, and acceleration. The students also need to understand vectors and vector addition.
oThe students work in groups of three to four.
oThis activity needs about 1 class period, could be more or have some sent home as homework if more examples are made up.
o Materials include worksheet and toy cars for the students to try out their solutions.
oThe students work in groups of three to four.
oThis activity needs about 1 class period, could be more or have some sent home as homework if more examples are made up.
o Materials include worksheet and toy cars for the students to try out their solutions.
Description and Teaching Materials
Start with a review of velocity and acceleration. Have students give examples of what a car that is accelerating looks like (a race car taking off, car at stop sign, and car turning are the ones I like to use) I also point out constant velocity when we talk about a velocity that isn't changing just so that situation doesn't confuse too many.
Go over vector addition if you haven't already. I tell my students that what we create through the vector addition in this activity is actually the new velocity so that they can look at the new velocity to discover what happened to the car's motion.
Give the students worksheet number one and work through the example and maybe number one with them.
The students can then work on the rest of the worksheet in pairs or groups with your help.
When they finish worksheet number one, give them worksheet two. Depending on how long you had to take with the introduction, this may wind up being homework.
I finish by drawing the situation on the white board and having the students indicate acceleration for which ever situation we're going through if the acceleration vector should point "towards the door" or "towards the wall" etc. so I can see who is understanding the concept. Doing this once or twice while they are working is a good way to see which group might need your help as well.
Velocity and Acceleration Vectors Worksheet part 1 (Microsoft Word 33kB Sep2 08)
Velocity and Acceleration Vectors Worksheet part 2 (Microsoft Word 34kB Sep3 08)
Go over vector addition if you haven't already. I tell my students that what we create through the vector addition in this activity is actually the new velocity so that they can look at the new velocity to discover what happened to the car's motion.
Give the students worksheet number one and work through the example and maybe number one with them.
The students can then work on the rest of the worksheet in pairs or groups with your help.
When they finish worksheet number one, give them worksheet two. Depending on how long you had to take with the introduction, this may wind up being homework.
I finish by drawing the situation on the white board and having the students indicate acceleration for which ever situation we're going through if the acceleration vector should point "towards the door" or "towards the wall" etc. so I can see who is understanding the concept. Doing this once or twice while they are working is a good way to see which group might need your help as well.
Velocity and Acceleration Vectors Worksheet part 1 (Microsoft Word 33kB Sep2 08)
Velocity and Acceleration Vectors Worksheet part 2 (Microsoft Word 34kB Sep3 08)
Teaching Notes and Tips
oI usually go step by step through the first one so that it isn't the process of the activity that slows people down.
oI collect worksheet number 1 before I give them worksheet number 2 because there are always those students who figure out that the situations are the same and just copy.
o I like to give them back their worksheets to correct so that they can see where they made errors and then since they already corrected everything, it is really quick for me to see where any problems are.
oI collect worksheet number 1 before I give them worksheet number 2 because there are always those students who figure out that the situations are the same and just copy.
o I like to give them back their worksheets to correct so that they can see where they made errors and then since they already corrected everything, it is really quick for me to see where any problems are.
Assessment
Can collect and correct the worksheets for assessment. Also, you can give the motion situation to the students and have them indicate which direction the acceleration vector would be in with their hands for a quick check on who is "getting it".
Standards
A solid understanding of the terms used in this lesson are necessary to understanding Newton's Laws, and gravity and so this lesson fits in with Grade 9-12, II. Physical Science, D. Motion