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Overview of types of immune responses. Difference between innate and adaptive immunity. Differences between humoral adaptive immunity and cell-mediated adaptive immunity.
Overview of types of immune responses. Difference between innate and adaptive immunity. Differences between humoral adaptive immunity and cell-mediated adaptive immunity.
The Earth behaves like a giant bar magnet and as such there is a magnetic field present around it. The Earth’s magnetic field is thought to be caused by flowing liquid metals in the outer core of the planet which causes electric currents and a magnetic field.
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 idea of the electric field, how it's useful, and explains how the electric field is defined.
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.
The force that acts across the air gaps between magnets is the same force that creates wonders such as the Aurora Borealis. In fact, magnetic effects pervade our lives in myriad ways, from electric motors to medical imaging and computer memory. In this chapter, we introduce magnets and learn how they work and how magnetic fields and electric currents interact.
In this lesson you will learn about:
Introduction to magnetism: Wikipedia article that provides an overview of the concept.
Forces at a distance are explained by fields (gravitational, electric, and magnetic) permeating space that can transfer energy through space. Magnets or electric currents cause magnetic fields; electric charges or changing magnetic fields cause electric fields.