G10 Q2 SCIENCE

• Andre-Marie Ampere - contributed in developing equations that showed the relationship of electricity and magnetism
• Heinrich Hertz - showed experimental evidence of electromagnetic waves and their link to light
• Hans Christian Oersted - demonstrated the magnetic effect based on the direction of the current
• Michael Faraday - formulated the principle behind electromagnetic induction
• James Clerk Maxwell - showed how a current carrying wire behaves like a magnet
• Electromagnetic Spectrum - is a continuum of electromagnetic waves arranged according to frequency and wavelength
• Radio waves - have the longest wavelengths and lowest frequencies
• microwaves - used in satellite communications because they can penetrate the ionosphere
• infrared waves - lie in the region beyond the red end of visible spectrum
• wavelength of infrared waves is too long to be visible to the naked eye
• Visible light - can be detected by the naked eye. Also known as light waves and only take a small portion of the entire electromagnetic spectrum
• ultraviolet waves - invisible radiation that lie beyond the violet end of the visible spectrum
• x-rays - have short wavelengths and high frequencies and are very penetrating.
• x-rays with long wavelengths can penetrate through flesh, but not bone
• gamma rays - high energy waves produced from nuclear reactions
• modulator - transforms AF signal and RF carrier wave to a modulated carrier wave
• microphone - converts sound wave to audio-frequency signal
• amplifier - magnify/increases energy of modulated carrier wave
• radio frequency oscillator - produces radio frequency carrier wave
• speaker - converts AF signal to sound energy
• demodulator - extracts AF signal from modulated carrier wave
• antenna - transmits and receives radio wave
• tuner - selects the frequency of the desired station