- Details
- Written by Krishnakali Gupta
- Parent Category: Science
- Category: Science 16-19
- Created: 22 November 2010
Hi everyone!
It is indeed a shame that I have failed to upload earlier, I did try but somehow I did not get as far as this uploading stage. But today since Ive managed, I want to literally sieze this oppurtunity to write a few words...
Right after my return from Jurmula, we started our session after the fall break. It was a good time for me to introduce the TA.
I gave my Grade 9 this task
You are stranded in the mountains in a house with unlimited wood. There is no electricity. So you have to generate electricity enough to run a computer for a period of approximately half hour.
The students responded better than what I had expected. (they were divided into three groups). Two of the groups came up with the idea of making steam to driving motor to making transformer etc. The route that I had anticipated they would adopt. What is interesting is what the third group went on to do. They wanted to make a battery. Using normal things found in the lab, they set about to make this battery. However, at one point they did not have access to a chemical, zinc sulphate. Undaunted, they chose to go ahead and prepare some zinc sulphate in the lab. They had a lot of fun. The hydrogen gas that came out as a by product and could have been left to simply escape, was trapped in balloons. So this diversion added to their learning.
right now this group has figured out that making one voltaic cell is not enough, as the electricity generated is too little. so they are designing to make three more and connect them in a series to see if the electricity generated by each can be added on.
Comments
Step 2. (Students)I have access to thermal energy. how can I turn it into electricity?
Step3. transformers are needed ( this is how they do it in the power stations )what do they burn? they burn non renewable energy, coal. We have another source (renewable, non renewable? these are some offshoots exlpored on the way)
Step 3. If we could have this thermal energy at our disposal to make a magnet rotate around a wire, an electric current would be produced, which would be useful for charging the battery of the computer (original task)
At this point they come up with an obstacle, namely what how can the heat or steam that we manage to generate, finally turn the motor in the trnasformer?
From there they go on to review their learning of how to make machines work....levers etc.
1. You're saying that the original task is Step 1 of the framework. At the same time, you wrote that students came up with quite a few ideas, right? If so, on what way is it step 1 of the framework where students are normally expected to be at a loss?
2. Step 2 of the framework is about the development of tools for copying with the challenging task that appeared in Step 1. What kind of tools did your students create? How did they apply them?
3. Step 3 is about different types of reflection - what exactly are the students reflecting on here? What are the outcomes?
Thanks in advance for your clarifications. Most probably I should just see more posts from you and then things will become clear.
Once they realized this they set upon investigating the different ways of doing this. Wood burns (everyone knows this, definitely in norway!)
Then going back.... how could they convert the heat generated into electricity?
There was a pause at this step. They then went on to investigate how coal burning plants generate electricity?
They then found that there are turbines involved... and so on.
It is interesting that one group by passed this line of thinking and wanted to make electricity using common salt (using the chemical energy locked in the common salt to make current in a wire.) They then went on to creating batteries, again founding their path on the fact that Energy is inter convertible.