Burning Question: How can I walk on ice?
Your task is to determine the relationship between the force being applied and the resulting reactionary force. Discuss with your team members how to identify each type of force as well as how to measure them.
Discuss with your team what the system is for this experiment. Does the system change from video to video? If so, explain how to identify the system in each video.
Make a data table of values your team will need to measure in order to determine the relationship between applied force and reactionary force.
Take measurements for each of the four videos. Graph applied force and reactionary force for each video. Which variable is independent and which is dependent?
Calculate the slope of the line for each graph. What number do you get? What is the significance of this number?
Analysis:
Describe the relationship between the force applied to a system and the reactionary force the system applies back.
Does this relationship hold true for all situations?
The Earth pulls on the Moon with a force of about 2.0x1020N. According to your observations, will the Moon pull on the Earth with greater than, less than, or equal to 2.0x1020N?
Imagine that your car breaks down and you have to push it to the service station. If you exert a force of 100N on your car, how much force does the car exert on you?
Two physics students are arguing. Marty claims that when he walks he is using his legs to push his mass forward. Gloria insists that the ground is pushing him forward. Discuss with your team the details of this argument. Write a brief argument where you pick one side or the other and give evidence to support your position on the following issue. “Is it possible for a system to push itself forward?”
Forces Between Carts in a Collision
Attach elastic metal bumpers to two carts. Observe the force on each cart during a collision.
How do the forces compare when the carts have the same mass?
How do the forces compare when the masses are unequal?
Reading Assignment Week 8
Pages 166-170
Practice Work Week 8
Lecture Videos Week 8