Infrared Waves

A : infrared waves are often called heat waves. R : Infrared waves vibrate not only the electrons, but entire atoms or molecules of a substance which increases the internal energy and temperature of the substance.

Match List - I (Electromagnetic wave type) with List - II (Its association/application) and select the correct option from the choices given below the lists: {:(,"List"1 , "List"2) , (1., "Infrared waves" , (i) "To treat muscular strain"), (2., "Radio waves" , (ii) "For broadcasting"), (3., "X- rays" , (iii) "To defect fracture of bones"), (4 ., "Ultraviolet rays" , (iv) "Absorbed by the ozone layer of the atmospher"):}

Which of the following has lowest frequency? Gamma rays, Radio waves, Infrared rays

Which of the following rays and waves do not belong to electromagnetic spectrum ? alpha rays , X rays, Ultraviolet rays , Radiowaves , Cathode rays , Ultrasonic waves, Infrared rays and Microwaves

Which of the following represents an infrared wavelength

Infrared lamps are used in restaurants to keep the food warm. The infrared radiation is strongly absorbed by water, raising is temperature and that of the food. If the wavelength of infrared radiation is assumed to be 1500nm , then the number of photons per second of infrared radiation produced by an infrared lamp that consumes energy at the rate of 100W and is 12% efficient only is y xx 10^(19) . Find the value of y .

Infrared lamps are used in restaurants to keep the food warm. The infrared radiation is strongly absorbed by water, raising its temperature and that of the food. If the wavelength of infrared radiationis assumed to be 1500 nm, and the number of quanta of infrared radiation produced per second by an infrared lamp (that consumes enregy at the rate of 100 W and is 12% effcient only) is (xx10^(19) , then the value of x is : (Given: h= 6.665xx10^(-34)J-s)

Arrange the following electromagnetic waves in the descending order of their wavelengths: (i) Microwaves (ii) Infrared rays (iii) Ultraviolet radiation (iv) Gamma rays Write one use each of any two of them.