Aim: - To learn about electricity Video notes:
- There are two types of electricity. They are static and current. Static electricity is an imbalance of electrical charges within an object or material. Current electricity is a flow of electricity - There are three types of sub-atomic particles: neutron, proton and electron. Neutron's have no electrical charge, protons have a positive charge, and electrons have a negative charge. - Electricity is the flow of electrons balancing out a difference in charge. - Electricity will always try to go on route with the least resistance. - In a closed circuit electrons flow towards the positive end of the battery. - Insulators are things that don't allow electricity to go through them such as ceramics and conductors are things that allow electricity to go through them such as gold. Aim: - To test how long the pendulum will swing for by releasing at different angles each time. Focus Question: Can you make a pendulum clock? A pendulum clock is a special type of old clock that was used before clocks were electronic. They work using a swinging pendulum that the user would wind up, and then the pendulum would swing. A pendulum continues to swing due to its continuous conversion between gravitational potential energy and kinetic energy. An object that continues to switch its energy between potential and kinetic is called a harmonic oscillator. Even though as the pendulum continues to swing energy is lost to air resistance, the bob take the exact same amount of time to complete one swing, no matter how much energy it has. This is simply because, with a higher angle comes a greater distance, but also a quicker swing time. As energy is lost and the angle becomes smaller, the pendulum also swings slower. This means that the period of the swing remains the same. The pendulum clock works around its swinging pendulum. Every time the bob completes a full swing, or returns to the point it was dropped from, it turns the second gear once, which turns the minute gear at 1/60 of the speed and therefore the hour hand at 1/60 the speed of the minute hand. In our experiment we set up a pendulum using a bob on a 60cm string hanging from a clamp attached to a retort stand. The setup can be seen in the scientific diagram below. Test Results: Unfortunately, we started at 45 degrees. The pendulum then swung for 30 minutes so we ran out of time to test the other angles of release. Conclusion/Discussion: Although we didn't finish our experiment, we were able to tell from other groups that the lower we release the pendulum, it will swing for less time. Lesson Summary:
- Experimented with pendulums - learnt that the period of each swing is exactly the same as before - Learn how a harmonic oscillator is an object that continuously transforms potential energy into kinetic energy and back again. Aim: - To test different types of fruit to see how much voltage they can produce. How does this work? Batteries are comprised of two different metals suspended in an acidic solution. With the Fruit-Power Battery, the two metals are zinc and copper. The zinc is in the galvanization on the nails, and the coins are actually copper-plated zinc. The acid comes from the citric acid inside each lemon. The two metal components are electrodes, the parts of a battery where electrical current enters and leaves the battery. With a zinc and copper setup, the electron flow is out of the coin (copper) and into the nail (zinc) through the acidic juice inside the lemon. In the exchange of electrons between the zinc and the copper over the acid bridge, copper accepts two electrons from zinc which accounts for the current. Which fruits produce the most voltage? Lemon - high voltage Potato - medium voltage Orange - low voltage Focus Question: How many oranges are needed to charge an iPhone? Approximately 2380 pieces of orange are required to charge an iPhone. Here are some images and videos from our experiment: Lesson Summary:
- Tested voltage outputs of potatoes, oranges and lemons. - Learnt how a fruit battery works. - Determined how many pieces of fruit were required to charge an iPhone. Aim: - To use experiments to show energy transformations. Experiment 1: In this experiment we were using battery packs to light up the different components and start the motor. By using the 100 ohm built-in variable resistor, we were able to control how bright the light was and how fast the fan spins. Above: The globe light Below: The LED light Experiment 2: In this experiment we span the wheel which had a rubber band connecting it to a generator which generated electricity which then powered the light. In the video below you can see the light glowing very faintly. Experiment 3: In this experiment we used a transformer to power the bell and make it ring. The video below explains how this works. Experiment 4: In this experiment we a transformer to power the lights which then powered the solar panel. The input voltage was 2 - 12 volts and by watching the video you can see how changing the brightness of the lights changes the voltage produced by the solar panel. The energy transformations taking place is electricity to light and then back to electricity. When the lights convert electricity into light, a waste product of heat is produced. Lesson Summary:
- we witnessed energy transformations using hands-on techniques. |
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