1) Here are some statements. Which is true ? A Sound travels at the same speed as light B Sound travels faster than the speed of light C Light travels faster than the speed of sound a) A b) B c) C 2) What are the units of frequency? a) m/s b) Hz c) m d) s 3) What is wavelength measured in? a) m/s b) Hz c) m d) s 4) Sound travels at 330 m/s. How long will it take to travel 990m? a) 0.333s b) 1s c) 2s d) 3s e) 4s f) 5s 5) Look at the wave. What is the amplitude of the wave and its wavelength? a) Amp = 1.2m, wavelength = 2m b) Amp = 2.4m, wavelength =2m c) Amp = 1.2m, wavelength =1m d) Amp = 2.4m, wavelength =1m 6) The law of reflection says that the angle of incidence will be equal to the angle of reflection. From which two points do we measure the angle of incidence? a) from the incident light ray to the normal b) from the mirror to the incoming light ray c) from the light beam to the reflected ray d) from the reflected ray to the normal 7) Light changes speed when going from one medium into another (e.g. air to glass) If it hits the surface at an angle it will bend. What is this known as? a) Reflection b) Refraction c) Diffraction d) Bending of light 8) Once the angle of reFRACTion is equal to 90 degrees rays begins to totally internally reFLECT. What is the name given to this angle which is different for different sunstances? a) 45 degrees b) angle of incidence c) angle of reflection d) Critical angle e) Angle of refraction 9) Which of these is NOT an advantage of optical fibres over copper wires? a) they carry more information b) they are cheaper to make c) they travel faster d) electrical interference is greatly reduced 10) What is the energy change that takes place in a microphone? a) sound to electrical b) electrical to sound c) sound to light d) sound to sound e) electrical to light 11) When transmitting audio signals with AM , it is modulated with a high frequency wave known as a...? a) piggyback wave b) traveller wave c) courior wave d) carrier wave e) tidal wave 12) Which part of a radio reciever strips the AM (or FM) wave into the original audio signal? a) aerial b) tuner c) decoder d) amplifier e) power supply f) loudspeaker 13) At is the speed of radio waves in air? a) 330m/s b) 1000m/s c) 200,000,000m/s d) 300,000,000m/s e) 330mph 14) NEED CALCULATOR. What is the wavelength of a radio wave with a frequency of 300kHz? a) 0.081m b) 8,100m c) 810,000m d) 0.81m e) 810 m 15) What colours mix together to give you yellow? a) red, green and blue b) red and green c) red and blue d) blue and green 16) Diffraction is when waves will bend around objects. What kind of waves will diffract more? a) long wavelengths b) short wavelengths 17) To pick up satellite signals you need a dish (curved refector). What type? a) Concave, focus b) convex, focus c) concave, centre d) convex, centre 18) Geostationary satellites stay above the same point in any part of the world you want a) True b) False 19) The period of a satellite can be increased by a) putting it into a lower orbit b) putting it into a higher orbit c) height does not affect the period of a satellite. 20) assuming that a satellite is directly above you at 36,000km. how long would it take radio waves to travel from you to it? Need Calcualtor a) 0.12s b) 0.24s c) 2400s d) 1200s

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