## Action-reaction! rocket – activity – teachengineering gas x directions

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Start with an in-class demonstration. For example, have a student or the teacher stand on a skateboard and throw a basketball. What happens? Have a student or the teacher throw a basketball filled with lead weights or similar, very heavy object (this could be dangerous; be careful not to fall). What happens? (Answer: The person rolls backwards on the skateboard.)

Or, as another demonstration: Pass around gas buddy three containers (such that students cannot see the contents), one filled with something light such as feathers or foam peanuts, one filled with something heavy such as lead weights and one filled with something in the middle such as rice or grains. Ask students which is heavier. Ask them what they think is inside. Tell them that the physical science electricity review worksheet heaviest one is heavier because it has a higher mass.

Rockets and rocket-propelled flight has been in use for more than 2,000 years. People in ancient China used gunpowder to make fireworks and rockets. In the past 300 years, people have gained a scientific understanding of how rockets work. Now, aerospace engineers use their understanding to make rockets fly farther, faster, higher and more accurately. Our understanding of how rockets work arises from Sir Isaac Newton’s three laws of motion. It is important for engineers to understand Newton’s laws because they not only describe gas bijoux soho how rockets work, they explain how everything that moves or stays still works!

This activity demonstrates all three of Newton’s laws of motion. The focus of the activity is Newton’s third law of motion, but the first and second laws are intrinsically involved with the motion of the rocket as well. The air pushing its way out of the balloon is an action force, and it causes an equal reaction, which is the movement of the balloon. The more air initially in the balloon, the further the balloon travels along the string because the action force is greater. By the same token, if only a small amount gas engine tom of air is initially in the balloon, the balloon travels a shorter distance.

Numbered Heads: Have students on each team pick numbers (or number off) so each z gas tecate telefono member has a different number. Ask students questions from the worksheet. Have the members of each team work together on the answer and everyone on the team must know the answer. Call a number at random. Students with that number raise their hands to answer the question. If not all the students with that number raise their hands, let the teams work a little longer. Encourage students to include terms that they have learned in the answers.

Have students fill up their balloons with water and repeat the experiment. Ask gas 89 them why the balloon moved so slowly (if at all) and why. (Answer: Because the water is heavy, it takes more force to move water than air, and the water spills out of the balloon slowly (compared to air), thus the reaction force is equally as slow as the action force. Note: This is messy! Make sure electricity in water pipes to follow the water-balloon with a bucket to catch the water or do this activity outside.

Have students re-engineer their balloon rockets again, adding extra features to make the balloon go further. Permit them to use more straw and tape, and more than one balloon. Conduct a race to see which engineering team built the best balloon rocket. Ask that team to explain why their design worked as it did, in terms of Newton’s three laws of motion.