# Newton's second law is the law of

## 2. Newton's law

### Curriculum reference

 Middle school 5 Realschule curriculum plus (I) 7/10 (II + III) 8/10 high school CurriculumPlus 8/10

### Notes on implementation

The experiment was carried out with the Cassy data acquisition system, but can just as easily be carried out with Vernier (ultrasonic sensor) or with Pasco. It is important that in addition to time-location diagrams, time-velocity diagrams can also be generated. Unfortunately, the time-location relationship always had to be shown in our program, so that reading the acceleration was only possible after the time-velocity diagram had been generated.
The display with a notebook is usually too small, so that a projector should be used. The videos were filmed in a darkened room in order to generate sufficient contrast for the recording of the projector. In class, the experiment can be carried out and projected under normal conditions in the classroom.
The runway should be well adjusted so that the measured values ​​do not deviate too much. The file used for recording measured values ​​with Cassy can be found here (right mouse click, "Save target as ...").

 Mass car: 500g Mass pull weights: 50g each Mass additional weights: 500g

Upper video: a proportional F

If you want to show the dependence of the acceleration on the accelerating force (video above), you have to ensure that the mass to be accelerated remains constant. The mass to be accelerated is made up of the mass of the car and the pieces of mass that accelerate the car by means of gravity. If you want to increase the accelerating force with an additional weight, this weight must have been on the cart beforehand. In our videos we limited ourselves to two different pulling forces in order not to let the experiment become any longer. Of course, you can initially weigh the car down with two 50g pieces and then work with three different pulling forces.

Lower video: a indirectly proportional m

You just have to note that the accelerated mass includes the wagon, additional weight and train weights. In the video two 50g weights were used as pull weights.

During the experiment, to repeat the laws of motion, reference can be made to the distance increasing quadratically with time.