**A teaching presentation in which the students observe qualitatively how speed is affected by the size of a force.**

This Teaching Presentation introduces the students to the effect forces have on the speed on an object.

Use this teaching resource when investigating force in science lessons.

This presentation covers the following concepts:

- Speed is the distance travelled in a set amount of time.
- More force will give an object greater speed.
- Greater mass requires more force to move.

A class discussion and independent task have been included at the end of the presentation.

Anonymous·Thanks for your prompt reply. That makes sense now. I had thought of changing the amount of air but not the number of straws. Thanks.

Paul (Teach Starter)·You're most welcome! We're always happy to help.

Anonymous·Hi Amy. I am looking at using this activity but Iâ€™m a bit confused to how students use a different design for the thrust apparatus. Could you give me an example of how they might do this please? Thanks.

Paul (Teach Starter)·Hi Robyn, The students are asked to design an apparatus that attaches a balloon to a model car. When the balloon is inflated and then released, it should push the car along. Students should vary their design to test how it affects the speed of the car. It is important to change only one variable in order to arrive at the best conclusions. For example, a student's apparatus may use one straw, four pieces of tape and a balloon. They could then change one aspect for one these materials e.g. use two straws, then three straws, inflate the balloon to three different levels. All other variables would stay the same i.e. if changing the number of straws, the air in the balloon and pieces of tape would need to be the same for each test. Please feel free to get in touch if you have any questions.