Tuesday, January 11, 2011

RAYS AND WAVES

• Gamma rays are considered the death rays.
• Gamma rays travel with the velocity of light
• Gamma rays have maximum penetrating power
• Shortest wavelength among alpha, beta and gamma is of gamma rays
• Laser rays are used in micro surgery
• Alpha radiations produce burns on human body
• Newton proved that sunlight consists of different colors
• Beta rays are fast moving electrons.
• Color with shortest wavelength is Blue
• Violet have shortest wave length and Red has longest wavelength (vibgyor)
• Red light’s wave length is 11800 waves/cm (< infra red)
• Least deviated color in prism is red
• Greatest deviated color in prism is indigo (chk violet)
• Violet light’s wave length is 23600 waves/cm (> ultra violet)
• Ultraviolet rays are less than 3000 deg: A
• Greatest value of wavelength is of infra red
• Visible waves are between 400-700 nanometers.
• MOTE = Million Tons of oil equivalent
• REM = Roentgen equivalent in man
• Transverse waves can only be produced in solids
• Longitudinal waves can be produced in solids, liquids and gases
• On passing thought food stuff, x-ray can kill bacteria
• Violet color of light t ravel thought glass with minimum speed
• There is no wavelength of light for color brown.
• White light is a mixture of all the colors in the rainbow.
• Blue has the shortest wavelength and red the longest.
• Radio waves also come from sun and outer space. Astronomers use radio telescope to hear them.
• Radar uses microwaves.
• Anything that is warm produces infrared waves including us. The hotter the thing the more IR.
• Infrared waves are used in TV remote control.
• X-rays have shorter wavelength and more energy than ultraviolet rays.
• Gamma rays come from radioactive materials. They are used to kill cancers.
• Without exposure to ultraviolet light our bodies would not be able to make vitamin D.
• UHF, ultra high frequency are radio waves used for TV broadcast
• Microwaves are used in radar, mobile phones, microwave oven, communication network
• Each light color is of different wavelength.
• Red light has the longest wavelength while violet light has the shortest.
• Waves with a longer wavelength than red light are invisible they are called infrared waves.
• Invisible Ultraviolet wave have wavelength shorter than violet light.
• Red, Blue, Green are prime colors.
• Red + Blue + Green = white
• The wavelength of visible light is between 1350-2500
• An object that reflects all the light looks white.
• Loud speaker converts electrical energy into sound energy.
• Light coloured clothes are generally worn in summer
• The electrical device which transform voltage : transformer
• A nuclear reaction in which two or more than two lighter nuclear are fused together to form a relatively heavier one : nuclear fusion
• The three colours combination which produces the sensation of white light : Red green and blue
• The clear sky looks blue because of dispersion of light
• When light waves travel from air to glass the wavelength and velocity variables are affected.
• Electrical lines of forces are imaginary.
• Frequency distinguishes ultrasound from normal audible sound. Its f > 20,000 Hz.

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