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Physics library
Course: Physics library > Unit 18
Lesson 4: Discovery of batteries- Zinc copper cell (reduction-oxidation)
- How to measure?
- Battery meter (galvanometer)
- How Many Turns?
- Electrolyte test (pure water vs. vinegar)
- Reverse electrodes (polarity)
- Electrolyte (strong acid test)
- Electrolyte (salt test)
- Electrode (distance test)
- Electrolyte (temperature test)
- Electrode (surface area test)
- Standard cell
- How much electrolyte does a single cell need?
- The battery and electromagnetism
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Reverse electrodes (polarity)
What happens to the deflection when we attach the penny and zinc in the opposite direction? Created by Brit Cruise.
Want to join the conversation?
What do penny and zinc have to do with the opposite direction of this?(1 vote)
As long as he metals are dissimilar, you'll get a compass reading. Each time you reverse your metal arrangement, you also reverse your compass reading.(4 votes)
Say the penny had been in your wallet for weeks and was going green. Would the outcome of this experiment change?(2 votes)
Yes, because the copper rust might insulate the whole thing.(1 vote)
I want to ask that basically what is polarity? Does it is related to water??(1 vote)- Polarity is the property of having poles or being polar.(2 votes)
oh why ? just change (what I don't know how to call) and then polar change. Woww
could anyone explain to me please?(1 vote)- What did Mr. Khan write at the end of the line? I could not see(1 vote)
- persiacooper and evelissepadilla you guys are being extremely rude and disrespectful. Please treat others the way you would want them to treat you.
Have a wonderful day! :D
adam.fu16 I will see, but quick frankly I couldn't see it that well either but i'll look again(1 vote)
does the vinegar or water make the compass move if yes how ?(1 vote)- What is a zinc, and why would a penny battle a zinc?(1 vote)
- May you please clarify your question so I could help you out?(1 vote)
what is the need for vinegar why not anything else(1 vote)- Vinegar is a weak acid that is both cheap and readily available.(1 vote)
Video transcript
இந்தக் காணொளியில் மின் தகடுகள் அமிலத்தில் மூழ்கும் போது உருவாகும் மின் அதிர்வைக் கோணத்தில் அளவிடப் போகிறோம். இது அமிலம் உடைய கோப்பை. இப்போது மின் தகடுகளை அமிலத்தில் மூழ்கச் செய்கிறோம். காந்த ஊசி மின் அதிர்வுக்கு ஏற்ப நகர்கிறது. அதன் கோணத்தைக் குறித்துக் கொள்கிறோம். இப்போது இணைப்பை மாற்றிப் பொருத்துகிறோம். மீண்டும் மின் தகடுகளை அமிலத்தில் மூழ்கச் செய்கிறோம். காந்த ஊசி வேறொரு கோணத்தில் நிற்கிறது. இந்தக் கோணத்தையும் குறித்துக் கொள்கிறோம். இந்தக் கோணமானது திரும்பிய நிலையில் உள்ளது.