#1667. The experiment about Newton's first law.

Science, level: Middle
Posted Sat Apr 15 21:32:34 PDT 2000 by Kyungsun Choi (kxc266@psu.edu).
state college
Materials Required: model car,brick 3,spring balance, record timer
Activity Time: 1 hour
Concepts Taught: Newton's first law of movement

Students conduct 2 kinds of experiments
1. The first experiment is about the relationship between acceleration and force. Students measure the velocity change depending on the force given to the model car. To measure the force, students will use the spring balance. At first, students measure the velocity change to pull the car with 5 N force. Students change the force. Next, students change the force to 10N and 15N. Students record the velocity change by record timer. The timer makes the dots on the paper with uniform time interval. So, the distance change of the dot reflect the velocity change. Students calculate the acceleration of each case. Finally, students can draw the graph to explain the relationship between force and acceleration.
2. The second experiment is about the relationship between acceleration and mass. Students will measure the change of the velocity depending on the weight of the car under the condition of uniform force. Given model car and 3 brick, students can change the weight of the car. At first, students conduct experiment putting one brick on the car. Next, the brick is increased 2 and 3. The procedure is same with first experiment. Students will measure the velocity change by record timer and draw the graph.
The experiment will be conducted in a group. Students present the results and infer the Newton's first law.