Compare designs that reduce the force in a collision
Grade 11 Science Worksheet

Circle the best answer, or write your answer on the line.
A 2 kg toy cart at 3 m/s must be stopped with an average force of no more than 15 N. How long must the stop last, Ari?
A 0.5 kg toy cart at 6 m/s must be stopped with an average force of no more than 5 N. How long must the stop last, Esme?
In the bar chart, what are the average forces for the hard and soft stops, Kira?
- Both 6 N
- Hard 120 N, soft 24 N
- Hard 24 N, soft 120 N
- Hard 0.3 N, soft 1.5 N
In the bar chart, how many times smaller is the soft stop's force, Luz?
Use the picture in question 3.
- 0.2 times smaller
- 5 times bigger
- 5 times smaller
- The same
Bumper tests on a 2 kg toy cart at 3 m/s (example data). Columns: bumper, stop time (s), average force (N), bounces back?, added mass (g). A, foam, 0.2, 30, no, 50; B, spring, 0.1, 120, yes, 80; C, wood, 0.02, 300, no, 40; D, thick foam, 0.4, 15, no, 150. Bumper tests on a 2 kg toy cart at 3 m/s (example data). Columns: bumper, stop time (s), average force (N), bounces back?, added mass (g). A, foam, 0.2, 30, no, 50; B, spring, 0.1, 120, yes, 80; C, wood, 0.02, 300, no, 40; D, thick foam, 0.4, 15, no, 150. Bumper tests on a 2 kg toy cart at 3 m/s (example data) bumper stop time (s) average force (N) bounces back? added mass (g) A, foam 0.2 30 no 50 B, spring 0.1 120 yes 80 C, wood 0.02 300 no 40 D, thick foam 0.4 15 no 150 Using the bumper table, with force under 50 N and added mass at most 100 g, why isn't D chosen, Milo?
- It stops the cart too slowly to count
- Its force is too high
- It adds 150 g, over the limit
- It bounces the cart back
Using the bumper table, a classmate picks C because it is lightest. Why does C fail, Noah?
Use the picture in question 5.
- Its 300 N force breaks the force limit
- It bounces the cart back
- It is too heavy
- It is the right pick, being lightest
Using the bumper table, a classmate picks D because its force is lowest. What should Pia point out?
Use the picture in question 5.
- D breaks the 100 g mass limit
- D's force is too high
- D bounces the cart back
- D wins on force, so pick it
Why should every bumper be tested with the same cart at the same speed, Ren?
- So the bumpers wear out evenly
- So only the bumper changes
- To make the test quicker
- To raise the force
Why should each bumper be tested several times, Tala?
- To change the cart's mass between runs
- To check the results are reliable
- To lower the force
- To make the cart faster
A very thin, soft foam bumper squashes completely flat in a test. What problem does that cause, Zee?
- The cart bounces back faster
- The cart stops suddenly at the end, with a big force
- Nothing; flat foam works well
- The force drops to zero