Energy 15. Chain Reactions!

 Today we finalized our model of the energy story in the Mini Rube Goldberg machine.  We have told much of the energy story when it shows up in motion and collisions.

Energy 14. Investigating Mass and Energy

One of the questions that came up during the Newton's Cradle investigation was whether heavier objects have more energy if they are moving at the same speed as lighter objects.  (We talked about how mass is how much matter an object has in it and that heavier objects have more mass.)  

So, today we investigated the relationship between the mass of a moving object and its energy. First, we weighed two balls.

Then, we released each ball on the Hot Wheels track. The ball hit a car parked in the same spot each time. We measured the distance that the car moved after the collision. We repeated the investigation with each ball five times.

They recorded all of the data, averaged the distances, and graphed the data.

The heavier ball moved the car much farther!  Moving objects with greater mass definitely have more energy!

Energy 13. Marble Energy Transfer

 Today we did a brief investigation with a red and blue marble, and the boys modeled the energy in each marble before and after the collision with energy bars. (from "Looking Through the Energy Lens" by Sally Chrissman, et al)

They had some really interesting arguments about what might have been happening to the energy! 

Energy 12. Adding the Newton's Cradle Investigations to the Summary Table

 We discusses the results from each of their investigations and added them to our summary table.

Energy 11. Discussing Investigations in a Scientists' Circle

 Today, I started by giving them some information about energy in collisions.  During the investigations, one student talked about the energy possibly becoming sound.  I decided that today would be a good day to let them know that in a collision, some energy is usually transferred to the surrounding air.  As a result, the air gets heated and sound is produced. (From NGSS PS3.B)

The boys wrote a paragraph based on these instructions:

Write a paragraph about your investigation. Describe your investigation. What were the results? How much do you trust the results and why? Try to explain your results using energy ideas.  What questions do you have now?

After the students wrote their paragraphs, they met in a scientists' circle to share their results and ask each other questions.

Two questions we want to investigate now are:

Do heavier objects add more energy?

If you only do two balls, will it last even longer?

 

Energy 10. Graphing the Data

 The boys finished collecting their data. They averaged the seconds that the Newtons Cradle kept going in each set of trials, and graphed their results.

Energy 9. Newton's Cradle Investigations

Before we explored the Newton's Cradle, a student asked, "Can we start it now and let it go all night?" "Let's try it!" I answered. They were very surprised to see how quickly the Newton's Cradle stopped!

Today they created their own investigations to answer the question, "How can I make the Newton's Cradle last longer before it stops?

The four hypotheses were:

I think that the Newtons Cradle will last longer if I release all of the balls at once.

I think that the Newtons Cradle will last longer if I release the ball from a greater height.

I think that the Newtons Cradles will last longer if I release more balls at once.

I think that the Newtons Cradles will last longer if I hold on to the three middle balls.

They will continue collecting data today!