At MAAS Flashcards
How many watts did the Boulton and Watt engine produce? Did it provide more power than the average family car?
It produces 11kW. The average family car produces more than that
What is a Geissler tube and where it is found?
It is a egg-shaped vessel which contains gases. Different amounts and types produces a myriad of colors and patterns of light.
They’re found in fluorescent lights, neon signs and plasma television screens
What is a Crookes tube and how is it related to X-rays?
It is a cavity used to demonstrate that electrons flow in a straight line. A cross inside obstructs the electrons, casting a shadow on the glass.
This phenomena is the basis for X-rays
How is a positive charge generated?
When electrons LEAVE a surface
How is a negative charge generated?
When electrons gather/build up on a surface
What are 2 machines used to store and generate electric charge?
- Kelvin’s electrometer
2. Electrostatic machine
How do clouds generate electricity?
Fierce winds cause the droplets and particles to rubb off each other. This results in a buildup of electric charge, with +ive charge accumulating on the top and -ive charge on the bottom of the cloud.
When the -ive charge is large enough it JUMPS to anything with a lesser charge such as to a building or ground
What are 2 types of electric generators?
- Delezenne’s circle.
This contraption uses a handle which rotates a ring which intersects Earth’s magnetic field. Due to Faraday’s law of electromagnetic induction, a current is induced in the wires - Bike lights.
Pedal power moves magnets to power the lights
Describe the operation of the plasma ball?
It contains a central electrode and a mixture of invisible gases. The electrode radiates a high voltage electric field which charges the gas molecules with static electricity. They are ionised.
When you touch the surface of the sphere, you provide a discharge path for the static charge. In their quest to traverse the discharge path, the electrons collide with the gas molecules, releasing energy in the form of light
What new solar cell technology did UNSW develop in 2016?
A new solar cell which splits the incoming light (using a filter) and sends it to two different solar cells
What’s the simplest battery?
An arrangement of plates or rods of different metals immersed in a liquid
Describe Alessandro Volta’s first battery.
The first battery was invented around 1800. It used stacks of zinc and copper discs separated by salty, moist cardboard which delivers the current.
Describe modern day batteries?
They are called dry cells. The electrolyte is a paste or substance rather than a liquid, increasing convenience and making them more compact
Elaborate on what an electromagnet is?
It is wire wound on a metal core. The magnetic field is controlled by the current that is delivered. It’s used in electric motors and generators
How does a compass work?
The needle in the compass is a small magnet that rotates freely. It aligns with the Earth’s magnetic North Pole, aiding in navigation.
