Asteroids, comets and meteors
These three short online lessons discuss asteroids, comets and meteors.
These three short online lessons discuss asteroids, comets and meteors.
You have learnt about static electricity where charged particles (electrons) can move from one object into another giving objects an overall charge. In this unit1 you will learn about current electricity. This is when a continuous flow of charge can be created using a circuit made of conducting wires and an energy source.
The flicker of numbers on a handheld calculator, nerve impulses carrying signals of vision to the brain, an ultrasound device sending a signal to a computer screen, the brain sending a message for a baby to twitch its toes, an electric train pulling into a station, a hydroelectric plant sending energy to metropolitan and rural users—these and many other examples of electricity involve electric current, which is the movement of charge. Humanity has harnessed electricity, the basis of this technology, to improve our quality of life.
Other objects in the solar system are discussed in this online textbook viz. asteroids, meteorites, comets and dwarf planets.
This short online resource elaborates on the difference between climate and weather and why understanding the climate is important.
This short online tutorial highlights the difference between weather and climate.