Portfolio Activity
This is a simple electromagnet.
Source: blueringmedia/123RF
Evaluate the experimental design of this experiment:
A group of students want to see if they can make an electromagnet that shows evidence of an electrical/magnetic field. They find a picture in a science book of how to make an electromagnet. First, they gather a battery, some copper wire, and a nail. They wrap the wire around the nail and attach the ends of the wire to the battery. They find a bunch of stuff in a desk: paperclips, erasers, stick pins, and so on. They put the electromagnet near each object and see what happens. Some objects move, and some don’t.
How will you evaluate the experimental design? What should you do first?
Remember that you are trying to decide whether the experiment provides evidence of magnetic/electrical fields. Would you answer: “Yes, the experiment would provide evidence of magnetic/electrical fields? Or would you answer: “No, the experiment would not provide evidence of magnetic/electrical fields.”
Next, you are looking for any area(s) where the plan could be modified to better meet its goal. Evaluate all the areas of the experimental design:
Hypothesis: What is the hypothesis of the experiment? Decide if the experiment is able to test the hypothesis. If so, how?
Materials: What are the materials listed in the experiment? Could the description of materials needed be improved? How?
Methods: What are the methods listed in the experiment? Could the directions be improved? How?
To evaluate the experimental design, first, we need to consider whether the experiment would provide evidence of magnetic/electrical fields. In this case, the experiment would indeed provide evidence of magnetic/electrical fields because they are testing the effects of the electromagnet on different objects.
Now, let's evaluate the areas of the experimental design:
Hypothesis: The hypothesis of the experiment is not explicitly stated in the given information. However, we can assume that the hypothesis is that when the electromagnet is near objects, they will exhibit magnetism or move. The experiment is able to test this hypothesis by observing the objects' responses to the electromagnet.
Materials: The materials listed in the experiment are a battery, copper wire, a nail, and various objects such as paperclips, erasers, and stick pins. The description of materials is sufficient, but it could be improved by specifying the type and voltage of the battery, the gauge of the copper wire, and other specific details to ensure accuracy and reproducibility.
Methods: The methods listed are to wrap the copper wire around the nail, attach the wire ends to the battery, and then observe the effects of the electromagnet on different objects. The directions could be improved by specifying the number of turns to wrap the wire around the nail, indicating the polarity of the battery connection, and providing a clear procedure for observing and recording the effects on the objects.
In conclusion, the experiment does provide evidence of magnetic/electrical fields. However, the design could be modified by explicitly stating the hypothesis, improving the description of materials, and providing clearer directions in the methods section.
Noncontact Forces Portfolio Reflect
Review your completed activities that are to be submitted to your teacher and consider the following:
Does you evaluation look at the three aspects of an experiment: hypothesis, materials, and methods?
Did you explain how to improve the design and why?
Write a reflection about your learning in this portfolio. Your reflection should be at least three sentences. Use the following sentence starters as a guide:
I feel confident about analyzing and using data to draw conclusions on electric and magnetic fields because…
It is challenging to evalutate an investigation exploring evidence of electric and magnetic fields because…
Examples I learned of noncontact forces are...
Upon reviewing my completed activities, I can confirm that my evaluation did consider the three aspects of an experiment: hypothesis, materials, and methods. I provided feedback and suggestions for improvement in each of these areas.
In terms of improving the design, I did explain how to make specific improvements. For example, I suggested specifying the type and voltage of the battery, detailing the gauge of the copper wire, and providing clearer instructions for observing and recording the effects on the objects.
Reflection:
I feel confident about analyzing and using data to draw conclusions on electric and magnetic fields because I have been able to effectively evaluate the experimental design and suggest improvements. By considering the hypothesis, materials, and methods, I have gained a deeper understanding of what makes a well-designed experiment in this context.
It is challenging to evaluate an investigation exploring evidence of electric and magnetic fields because there are multiple factors to consider, such as the specific materials used, the clarity of instructions, and the completeness of the experimental design. However, through practice and analysis, I have developed the skills to critically evaluate and provide suggestions for improvement.
Examples I learned of noncontact forces are the effects of an electromagnet on different objects, the interaction between charged particles, and the repulsion or attraction between magnets. These examples have helped me comprehend the concept of noncontact forces and their role in various phenomena.