Advertisements
Advertisements
प्रश्न
Answer briefly.
What is a carrier wave?
Advertisements
उत्तर
The high-frequency waves on which the signals to be transmitted are superimposed are called carrier waves.
APPEARS IN
संबंधित प्रश्न
What role dose infra-red radiation play in physical therapy?
To which part of the electromagnetic spectrum does a wave of frequency 5 × 1011 Hz belong?
The small ozone layer on top of the stratosphere is crucial for human survival. Why?
State an additional use of the X-rays waves
What do you understand by the statement, "Electromagnetic waves transport momentum"?
State Moseley's law
What is the range of the wavelength of the following electromagnetic waves?
(a) Ultraviolet
Name the waves used for taking photographs in dark.
Name the waves of wavelength nearly 0.1 nm.
What are ultraviolet radiations?
Name of physical quantity which remains same for microwaves of wavelength 1 mm and UV radiations of 1600 Å in vacuum.
The electric current in an X-ray tube (from the target to the filament) operating at 40 kV is 10 mA. Assume that on an average, 1% of the total kinetic energy of the electron hitting hte target are converted into X-rays.
(a) What is the total power emitted as X-rays and (b) how much heat is produced in the target every second?
Heat at the rate of 200 W is produced in an X-ray tube operating at 20 kV. Find the current in the circuit. Assume that only a small fraction of the kinetic energy of electrons is converted into X-rays.
The Kα and Kβ X-rays of molybdenum have wavelengths 0.71 A and 0.63 A respectively. Find the wavelength of Lα X-ray of molybdenum.
(Use Planck constant h = 6.63 × 10-34 Js= 4.14 × 10-15 eVs, speed of light c = 3 × 108 m/s.)
A free atom of iron emits Kα X-rays of energy 6.4 keV. Calculate the recoil kinetic energy of the atom. Mass of an iron atom = 9.3 × 10−26 kg.
(Use Planck constant h = 6.63 × 10-34 Js= 4.14 × 10-15 eVs, speed of light c = 3 × 108 m/s.)
Continuous X-rays are made to strike a tissue paper soaked with polluted water. The incoming X-rays excite the atoms of the sample by knocking out the electrons from the inner shells. Characteristic X-rays are analysed and the intensity is plotted against the wavelength. Assuming that only Kα intensities are detected, list the elements present in the sample from the plot. Use Moseley's equation v − (25 × 1014Hz)(Z − 1)2.
(Use Planck constant h = 6.63 × 10-34 Js= 4.14 × 10-15 eVs, speed of light c = 3 × 108 m/s.)
State three properties of infrared radiations similar to that of visible light.
Name the radiations used for the detection of fracture in bones.
Choose the correct option.
How does the frequency of a beam of ultraviolet light change when it travels from air into glass?
Solve the numerical problem.
Calculate the wavelength in nm of an X-ray wave of frequency 2.0 × 1018 Hz.
Name the e.m. waves which are suitable for radar systems used in aircraft navigation. Write the range of frequency of these waves.
The fundamental frequency of an open organ pipe is 300 Hz. The first overtone of this pipe has same frequency as first overtone of a closed organ pipe. If speed of sound is 330 m/s, then the length of closed organ pipe is:
Microwaves are electromagnetic waves with frequency in the range of.
The ozone layer absorbs
A radio can tune to any station in the 7.5 mHz to 12 MHz band. What is corresponding wave length band.
All components of the electromagnetic spectrum in a vacuum have the same ______
Write two uses of the following radiation.
Gamma rays
Identify the electromagnetic wave whose wavelength range is from about 10-12 m to about 10-8 m. Write one use of this.
What is the wavelength range of electromagnetic radiation used in radio broadcast?
