Teachers can give young students an early introduction to linear motion concepts by creating a rocket car from common household items. Provide Styrofoam trays for students to draw and cut out a rectangle that is 4 inches by 9 inches and four circles that are each 4 inches in diameter. While students cut out their shapes, distribute balloons and flexible plastic drinking straws. Demonstrate how to slide the open end of the balloon over one end of the straw. Tape around the connection point securely to create a tight seal. Place the body of the straw lengthwise through the center of the rectangle, placing two strips of tape across the middle of the rectangle to hold the straw in place. Attach the circles as the car's wheels by driving a straight pin through the center of each circle into the edge of the rectangle. Leave a little space so the wheels spin easily. Students will blow through the straw to inflate their balloons and pinch off the end of the straw until it is time to launch the car. Cars should be lined up on a smooth surface and straws released at the same time. Discuss Newton's Third Law and ask students to identify the action and reaction in the experiment.
Elementary and intermediate teachers can help students understand the concepts of gravity, force and friction as well as their impact on linear motion with a simple and fun experiment involving the classic toy car. Educators will need a ramp at least 2 yards long with a gradual slope. This can be made from a section of plywood propped up by a few textbooks at one end. At the end of the ramp, place strips of fine sandpaper to line the last six inches of the ramp and attach with masking tape. Release a toy car from the top of the ramp and record the amount of time it takes the car to reach the end of the ramp. Repeat the experiment, changing the sandpaper each time with sheets of different grit size. After testing medium and coarse ground, extend the sandpaper coverage of the ramp to 12 inches, 24 inches and 36 inches. Record the time of completion during each run and discuss how friction impacts an object's linear motion in terms of acceleration and speed.
Build ramps of different lengths and heights for use in a simple classroom experiment that will help high school students calculate displacement and velocity. Students should release a golf ball from the top of each ramp and record the amount of time it takes the ball to run the length of the ramp, as well as the amount of time it takes the ball to stop after leaving the ramp. Students will need to measure the base and height of the ramp to determine the slope, then use the velocity formula to determine the speed of the ball over the course. Discuss the impact of the incline and ramp length on the linear motion of the golf ball.
High school instructors should divide students into groups of six and give two meter-sticks and two stopwatches to each group. Have students measure a distance of 100 meters, leaving one group member each at the beginning and end points as markers. Three students should line up at the starting position. One should be on foot, another should ride a bicycle and the third should wear roller skates. The last student should stand at the endpoint with a stopwatch and pencil to record results. Have each student propose a hypothesis about the outcome of the experiment. The three students should race from the start to the finish point. Teachers should lead a discussion about force and the relationship between circular motion and linear motion.