Why are the electrostatic fields between the electron gun  elements called lenses?

1 Answer

Answer :

Because they bend electron streams in much the same manner  that optical lenses bend light rays.

Related questions

Description : What will be the effect upon an electron traveling in the opposite direction to the lines of force in an electrostatic field?

Last Answer : The electron will be accelerated.

Description : An electron moves into the electrostatic field between a positive charge and a negative charge. Toward which charge will the electron move?

Last Answer : Toward the positive charge.

Description : An electron moves into the electrostatic field between a positive charge and a negative charge. Toward which charge will the electron move?

Last Answer : Toward the positive charge.

Description : What portion of an electron gun causes the electrons to accelerate or decelerate?

Last Answer : The buncher grids.

Description : The polarization of a radio wave: A. Is perpendicular to the electrostatic field of the antenna B. Is the same direction as the electrostatic field of the antenna. C. Is the same direction ... field of the antenna. D. Is perpendicular to both the electrostatic and magnetic fields of the antenna.

Last Answer : B. Is the same direction as the electrostatic field of the antenna.

Description : What is the relationship in degrees of the electrostatic and electromagnetic fields of an antenna? A. 0 degree B. 45 degrees C. 90 degrees D. 180 degrees

Last Answer : C. 90 degrees

Description : Which of the following statements is not valid in case of conductors in electrostatic fields? A) The static electric field intensity inside a conductor is zero B) The static electric field intensity at ... the surface C) The conductor surface is an equivalent potential surface D) None of the above

Last Answer : Which of the following statements is not valid in case of conductors in electrostatic fields? A) The static electric field intensity inside a conductor is zero B) The static electric field intensity at ... the surface C) The conductor surface is an equivalent potential surface D) None of the above

Description : In what way do magnetic lines of force differ from electrostatic lines of force?

Last Answer : Electrostatic lines of force do not form closed loops

Description : In what direction are electrostatic lines of force drawn?

Last Answer : Leaving positive, entering negative

Last Answer : The space between and around charged bodies.

Description : A MOSFET can be damaged by an electrostatic discharge at approximately what minimum potential?

Last Answer : 35 volts.

Description : At approximately what minimum voltage potential should you be able to feel an electrostatic discharge?

Last Answer : 3,500 to 4,000 volts.

Description : State four characteristics of electrostatic lines of force

Last Answer : a charged particle in straight lines and do not form closed loops. c. They have the ability to pass through any known material. d. They have the ability to distort the orbits of electrons circling the nucleus.

Description : State four characteristics of electrostatic lines of forceNEETS

Last Answer : a. They are polarized from positive to negative. b. They radiate from a charged particle in straight lines and do not form closed loops. c. They have the ability to pass through any known material. d. They have the ability to distort the orbits of electrons circling the nucleus.

Description : An electron microscope gives higher magnification than an optical microscope, because: (1) It uses more powerful lenses (2) the velocity of electron is smaller than that of visible (3) the ... particles (4) the wavelength of electrons is smaller as compared to the wavelength of visible light

Last Answer : (4) the wavelength of electrons is smaller as compared to the wavelength of visible light Explanation: An electron microscope uses a beam of electrons to illuminate a specimen and produce a ... photons. Magnification is the process of enlarging something only in appearance, not in physical size.

Description : An electron microscope gives higher magnifications than an optical microscope because - (1) The velocity of electrons is smaller than that of light (2) The wavelength of electrons is smaller as ... have more energy than the light particulars (4) The electron microscope uses more powerful lenses

Last Answer : (2) The wavelength of electrons is smaller as compared to the wavelength of visible light Explanation: An electron microscope is a microscope that uses a beam of accelerated electrons as a spume ... a higher resolving power than a light microscope and can reveal the structure of smaller objects.

Description : Electron microscope has a high resolution power. This is due to (a) electromagnetic lenses (b) very low wavelength of electron beam (c) low wavelength of light source used (d) high numerical aperture of glass lenses used.

Last Answer : (b) very low wavelength of electron beam

Description : An electron microscope gives higher magnifications than an optical microscope because : (1) The velocity of electrons is smaller than that of light (2) The wavelength of electrons is smaller as ... have more energy than the light particulars (4) The electron microscope uses more powerful lenses 

Last Answer : The wavelength of electrons is smaller as compared to the wavelength of visible light

Description : An electron microscope gives higher magnification than an optical microscope, because : (1) it uses more powerful lenses (2) the velocity of electron is smaller than that of visible light (3) ... particles (4) the wavelength of electrons is smaller as compared to the wavelength of visible light

Last Answer : the wavelength of electrons is smaller as compared to the wavelength of visible light

Description : What shape do electron probability fields have when they are unbound?

Last Answer : FireMadeFlesh What a fascinating question. An unbound electron does not exhibit quantized energy levels. However, it does exhibit the wave/particle duality that photons and other unbound particles do. That doesn't close the ... I can bring to the party, and this is a party I want to attend. :-)

Description : What composite field (composed of E and H fields) is propagated into free space?

Last Answer : Radiation field.

Description : What composite field (composed of E and H fields) is found stored in the antenna?

Last Answer : Induction field.

Description : Which two composite fields (composed of E and H fields) are associated with every antenna?

Last Answer : Induction field and radiation field.

Description : To propagate energy down an arm of a hybrid ring duplexer, the two fields at the junction of the arm and the ring must have what phase relationship?

Last Answer : 180 degrees out of phase

Description : Why should you never place floppy disks near telephones or other electronic equipments that generate magnetic fields?

Last Answer : Magnetic fields can destroy the data on a disk.

Description : How many fields make up a frame?

Last Answer : Two.

Description : Electron are emitted from an electron gun at almost zero velocity and are accelerated by an electric field `E` through a distance of `1.0m` The electr

Last Answer : Electron are emitted from an electron gun at almost zero velocity and are accelerated by an electric field ... .5 nm` may be emitted by the hydrogen?

Description : An electron gun emits `2.0xx10^(16)` electrons per second. What is the associated current ?

Last Answer : An electron gun emits `2.0xx10^(16)` electrons per second. What is the associated current ?

Description : Which of the following is not a part of a CRT? (1) Phosphor screen (2) Shadow mask (3) Electron gun (4) Gas plasma

Last Answer : (4) Gas plasma Explanation: The cathode ray tube (CRT) is a vacuum tube containing an electron gun (a source of electrons or electron emitter) and a fluorescent screen used to view images. Colour tubes ... stripes (as in aperture grille designs) or clusters called "triads" (as in shadow mask CRTs).

Description : A circuit which develops voltage across the horizontal deflection plates is known as a) Time base generator b) Electron gun c) Thermionic diode d) Zener diode

Last Answer : a) Time base generator

Description : Which of the following is/are the components of a CRT ? (a) Electron Gun (b) Control Electrode (c) Focusing Electrode (d) Phosphor Coated Screen Codes : (A) (a) and (d) (B) (a), (b) and (d) (C) (a), (b), (c) and (d) (D) (a), (c) and (d) 

Last Answer : (C) (a), (b), (c) and (d)

Description : Which of the following statement(s) is/are correct? (1) Persistence is the term used to describe the duration of phosphorescence. (2) The control electrode is used to turn the electron beam on and off. (3) ... which are focussed into a narrow beam directed at the face of CRT. (4) All of the above. 

Last Answer : All of the above.

Description : Which of the following is not a part of a CRT ? (1) Phosphor screen (2) Shadow mask (3) Electron gun (4) Gas plasma

Last Answer : Gas plasma

Description : In a CRO which of the following is not a part of electron gun: (1) Cathode (2) Grid (3) Accelerating anode (4) X–Y plates 

Last Answer : In a CRO which of the following is not a part of electron gun: X–Y plates 

Description : A soldering gun should NOT be used on what components?

Last Answer : Electronic components, such as resistors, capacitors, and transistors.

Description : What happens if a soldering gun switch is pressed for periods longer than 30 seconds?

Last Answer : It will overheat and could burn the insulation of the wire being soldered.

Description : Consider the following statements for priority queue: S1: It is a data structure in which the intrinsic ordering of the elements does determine the result of its basic operations. S2: The elements of a priority queue ... . (C) SI is incorrect and S2 is correct. (D) Both S1 and S2 are correct.

Last Answer : (D) Both S1 and S2 are correct.

Description : The resonant frequency of electron wobble can be changed by variation of what force?

Last Answer : The applied magnetic field.

Description : Which of the two types of electron motion (orbital movement and electron spin) is more important in the explanation of magnetism?

Last Answer : Electron spin.

Description : What effect does closer spacing of plates have on the electron beam?

Last Answer : A greater deflection angle.

Description : What effect does closer spacing of plates have on the electron beam?

Last Answer : A greater deflection angle.

Description : What effect do longer deflection plates have on the electron beam?

Last Answer : A greater deflection angle.

Description : The electron beam in a CRT is made to sweep from left to right across the screen. What tube element causes this sweeping motion?

Last Answer : The horizontal-deflection plate.

Description : What term is used for the ability of a spot on a CRT screen to continue to glow after the electron bean has struck it and moved away?

Last Answer : Persistence.

Description : What are two advantages that gas-filled tubes have over conventional electron tubes?

Last Answer : a. They can carry more current. b. They maintain a constant IR drop across the tube

Description : Why is electron flow with the arrow in the symbol of a Zener diode instead of against the arrow as it is in a normal diode?

Last Answer : Because Zener diodes are operated in the reverse bias mode.

Description : What term is used to describe the definite discrete amounts of energy required to move an electron from a low shell to a higher shell?

Last Answer : Quanta.

Description : State one requirement of an electron tube, which does not exist for semiconductors, that makes the tube less efficient than the semiconductor.

Last Answer : The electron tube requires filament or heater voltage, whereas the semiconductor device does not; consequently, no power input is spent by the semiconductor for conduction.

Description : What type of deflection is preferred for a crt electron beam?

Last Answer : . Electromagnetic.

Description : In an electron tube regulator, the electron tube replaces what component?

Last Answer : Variable resistor.