GOAL Students will investigate how to slow an object’s speed as it travels down a ramp. MATERIALS Paper Pencils Cardboard (cut into 20cm × 30cm size, one per team) Glue Felt strips Sandpaper strips Aluminum foil strips Quarter (one per team) Paper Towels Masking tape Stopwatch Teacher Setup: Make sure each stack pf books for the ramp must be an equal 12cm high Students work in teams of 2 METHOD Step 1: One student will act as the “slider,” while the other student will be the “timer.” Step 2: The “slider” will slide (not roll) a coin (the “vehicle”) down their cardboard ramp while the “timer” uses a stopwatch to record how much time it takes for the quarter to reach the end of the ramp. Have the “timers” record the time for each run on a piece of paper. After three runs, have teams calculate the average time. Allow 5 minutes for the test runs. Step 3: Teams choose materials to use on their cardboard ramp that will slow their vehicle as it moves down the ramp. Chosen materials should be glued to the cardboard ramp. Teams will have 10 minutes for this section. Step 4: Have teams repeat step 2 above to see how extra friction between the surface of the ramp and the coin affected its travel time. Times for three runs should be recorded and then used to determine an average time. Step 5: Finally, have teams find the difference between the averages of two sets of ramp runs. The team whose ramp adjustments were most effective in slowing their vehicles will be the team with the greatest difference in average times. Tiebreaker: In the event of a tie, the team that used the least material to slow their vehicle will be the winner.
Before the activity, set up an area where the ramp testing will take place. To ensure the inclines are all the same, use a stack of books 12 cm tall that the cardboard pieces will rest against to create the ramp. If each team cannot have its own stack of books, teams can take turns. Be sure teams understand how to time their coins as they move down the ramp. Demonstrate how to start with the coin flush with the top of the cardboard. Timing should begin when the coin is released and should be stopped when the coin reaches the end of the cardboard. Having all teams timing in the same way is important for the challenge portion of this activity. Briefly review how to determine averages. Depending on grade level, the facilitator may need to calculate average times for each team. Google Slides with Teaching Resources: https://docs.google.com/presentation/d/1viDGpVZg9IN6FO7R5w7mXwuS5ghvzrIKYR6aeRv-MrE/edit?usp=sharing Activity sourced from: https://stemplayground.org/activity-sheet/?a=7394