Students build their own small-scale model roller coasters using pipe insulation and marbles, and then analyze them using physics principles learned in the associated lesson. They examine conversions between kinetic and potential energy and frictional effects to design roller coasters that are completely driven by gravity. A class competition using different marbles types to represent different passenger loads determines the most innovative and successful roller coasters.

With a simple demonstration activity, students are introduced to the concept of friction as a force that impedes motion when two surfaces are in contact. Then, in the Associated Activity (Sliding and Stuttering), they work in teams to use a spring scale to drag an object such as a ceramic coffee cup along a table top or the floor. The spring scale allows them to measure the frictional force that exists between the moving cup and the surface it slides on. By modifying the bottom surface of the cup, students can find out what kinds of surfaces generate more or less friction. They also discover that both static and kinetic friction are involved when an object initially at rest is caused to slide across a surface.

Using the same method for measuring friction that was used in the previous lesson (Discovering Friction), students design and conduct experiments to determine if the amount of area over which an object contacts a surface it is moving across affects the amount of friction encountered.

Using the same method for measuring friction that was used in the previous lesson (Discovering Friction), students design and conduct an experiment to determine if weight added incrementally to an object affects the amount of friction encountered when it slides across a flat surface. After graphing the data from their experiments, students can calculate the coefficients of friction between the object and the surface it moved upon, for both static and kinetic friction.

Student groups are provided with a generic car base on which to design a device/enclosure to protect an egg on or in the car as it rolls down a ramp at increasing slopes. During this in-depth physics/science/technology activity, student teams design, build and test their creations to meet the design challenge, and are expected to perform basic mathematical calculations using collected data, including a summative cost to benefit ratio.

Learn about conservation of energy with a skater dude! Build tracks, ramps and jumps for the skater and view the kinetic energy, potential energy and friction as he moves. You can also take the skater to different planets or even space!

Learn about conservation of energy with a skater dude! Build tracks, ramps and jumps for the skater and view the kinetic energy, potential energy and friction as he moves. You can also take the skater to different planets or even space!

Students will: Predict the kinetic and potential energy of objects Design a skate park Examine how kinetic and potential energy interact with each other

This activity utilizes hands-on learning with the conservation of energy and the interaction of friction. Students use a roller coaster track and collect position data. The students then calculate velocity, and energy data. After the lab, students relate the conversion of potential and kinetic energy to the conversion of energy used in a hybrid car.

Based on what they have already learned about friction, students formulate hypotheses concerning the effects of weight and contact area on the amount of friction between two surfaces. In the Associated Activities (Does Weight Matter? and Does Area Matter?), students design and conduct simple experiments to test their hypotheses, using procedures similar to those used in the previous lesson (Discovering Friction). An analysis of their data will reveal the importance of weight to normal friction (the friction that occurs as a result of surface roughness) and the importance of surface area to the friction that occurs between smooth surfaces due to molecular attraction. Based on their data, students will also be able to calculate coefficients of friction for the materials tested, and compare these to published values for various materials.

Students use wood, wax paper and oil to investigate the importance of lubrication between materials and to understand the concept of friction. Using wax paper and oil placed between pieces of wood, the function of lubricants between materials is illustrated. Students extend their understanding of friction to bones and joints in the skeletal system and become aware of what engineers can do to help reduce friction in the human body as well as in machines.

Explore pressure in the atmosphere and underwater. Reshape a pipe to see how it changes fluid flow speed. Experiment with a leaky water tower to see how the height and water level determine the water trajectory.

HyperDocs are GoogleDocs that provide an interactive experience for students to explore linked resources about a topic.  This HyperDoc, created by Angela Wilson, provides students YouTube videos, interactive simulations, StudyJams, and games all about force, motion, and gravity.  **Please be sure to make a copy of the Doc before using.**

In the first of two lessons of this curricular unit, students are introduced to the concept of friction as a force that impedes motion when two surfaces are in contact. Student teams use spring scales to drag objects, such as a ceramic coffee cup, along a table top or the floor, measuring the frictional force that exists between the moving object and the surface it slides on. By modifying the bottom surface of the object, students find out what kinds of surfaces generate more or less friction. They also discover that both static and kinetic friction are involved when an object initially at rest is caused to slide across a surface. In the second lesson of the unit, students design and conduct experiments to determine the effects of weight and surface area on friction. They discover that weight affects normal friction (the friction that results from surface roughness), but for very smooth surfaces, the friction due to molecular attraction is affected by contact area.

Explore the forces at work when you try to push a filing cabinet. Create an applied force and see the resulting friction force and total force acting on the cabinet. Charts show the forces, position, velocity, and acceleration vs. time. View a Free Body Diagram of all the forces (including gravitational and normal forces).

Explore the forces at work when you try to push a filing cabinet. Create an applied force and see the resulting friction force and total force acting on the cabinet. Charts show the forces, position, velocity, and acceleration vs. time. View a Free Body Diagram of all the forces (including gravitational and normal forces).

Explore the forces at work in a tug of war or pushing a refrigerator, crate, or person. Create an applied force and see how it makes objects move. Change friction and see how it affects the motion of objects.

Explore the forces at work when you try to push a filing cabinet. Create an applied force and see the resulting friction force and total force acting on the cabinet. Charts show the forces, position, velocity, and acceleration vs. time. View a Free Body Diagram of all the forces (including gravitational and normal forces).

Students take a closer look at cars and learn about some characteristics that affect their energy efficiency, including rolling resistance and the aerodynamics of shape and size. They come to see how vehicles are one example of a product in which engineers are making changes and improvements to gain greater efficiency and thus require less energy to operate.

Learn how friction causes a material to heat up and melt. Rub two objects together and they heat up. When one reaches the melting temperature, particles break free as the material melts away.