05-01-2018, 04:47 PM
Cosmic ravs
*The rays which appears to be originated from outside of the earth is called cosmic rays .
*Cosmic rays were discovered by Victor Hess.
Infrared ravs
*Infrared ray was discovered by William Herschel.
*Waves used in TV remotes
Ans : Infrared
* Waves used in distant photography
Ans : infrared Rays
*The heat of the sunlight is due to
Ans : Infrared Rays
Ultaviolet rays
*Rays used for detecting the adulterations in ghee and is also used for identifying the counterfeit currency
Ans : UV Rays
*Ray used to disinfect equipments used for operation
Ans : UV Rays
*The ray that causes sunburn
Ans : Ultraviolet rays
HEAT
*Transfer of kinetic energy from one medium or object to another or from an energy source to a medium or object
Ans : Heat
*The study of materials and phenomena at low temperature
Ans : Cryogenics
*Heat is a form of energy that gives us the sensation of hotness or coldness.
*The degree of hotness or coldness of a body is defined as temperature.
*Heat is measured in the unit of Joule (J).
*Calorie was the unit, formerly used to measure heat.
*One calorie = 4. 2 Joules
*One calorie is the amount of heat required to raise the temperature of 1 gm of water by 1°C.
*As we go up the atmosphere, the temperature decreases.
*A black surface absorbs more heat than any other colours.
*Device used to detect heat radiation is called
Ans : Thermocouple
*The amount of heat required to raise the temperature of unit mass of a substance by 1°C is known as specific heat .capacity
*Water has the highest specific heat.
*Specific heat of water is 4185 J/KgK.
*Specific heat of water at 15°C is 1 calorie per gram Celsius.
*Specific heat of water is minimum at 37°C.
*Element with the highest specific heat is Hydrogen.
*Critical temperature is the temperature above which a gas cannot be liquified even when more pressure is exerted.
*Temperature at which Ice melts (Icepoint) =0°C = 273 K = 32°F
*Temperature at which water boils (Steam point) = 100°C - 373 K - 212°F
*Absolute Zero =' OK =-273.15°C
*Temperature which shows same measurement in Celsius and Fahrenheit scale - -40
*Temperature which shows same measurement in Farenheit and Kelvin scale = 574.25
*Fraction of volume of ice seen outside when it is immersed in water - 10.5%