A semi conductor is doped with impurities of 3 atoms e.g. Boron. Since group 3 atoms provide only 3 electrons for bonding, a hole is left in the structure without an electron. This hole results to holes becoming the majority charge carriers hence p-type semi-conductors.
joseph rimiru answered the question on December 12, 2017 at 19:17
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State three advantages of using GM tube instead of a diffusion cloud chamber to detect radiations from radiations from radioactive substance.
(Solved)
State three advantages of using GM tube instead of a diffusion cloud chamber to detect radiations from radiations from radioactive substance.
Date posted:
December 12, 2017
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Answers (1)
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Explain why some of the tracks formed in a diffusion chamber are observed to be:
a. Short
b. Straight
(Solved)
Explain why some of the tracks formed in a diffusion chamber are observed to be:
a. Short
b. Straight
Date posted:
December 12, 2017
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Answers (1)
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The half life of a radioactive substance is 12 years. Determine the time it would take to decay to 12.5% of it original value....
(Solved)
The half life of a radioactive substance is 12 years. Determine the time it would take to decay to 12.5% of it original value.
Date posted:
December 12, 2017
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Answers (1)
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An element x has a half life of 3.83 days. If a sample of this element is found to disintegration per second at a particular...
(Solved)
An element x has a half life of 3.83 days. If a sample of this element is found to disintegration per second at a particular time. Determine its activity rate after 19.15 days.
Date posted:
December 12, 2017
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Answers (1)
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Short thick track were observed when a radiation was released into a diffusion cloud chamber. State with a reason the type of radiation was...
(Solved)
Short thick track were observed when a radiation was released into a diffusion cloud chamber. State with a reason the type of radiation was detected.
Date posted:
December 12, 2017
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Answers (1)
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A certain sample of radioactive material has a half life of 130 days and has 1.0 x 10^20 atoms initially. Determine the number of radioactive...
(Solved)
A certain sample of radioactive material has a half life of 130 days and has 1.0 x 10^20 atoms initially. Determine the number of radioactive atoms that have decayed after 390 days.
Date posted:
December 11, 2017
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Answers (1)
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A radioactive Cobalt 60 has a half life of 5.25 years. What fraction of the original atoms in a sample will remain after 21 years?
(Solved)
A radioactive Cobalt 60 has a half life of 5.25 years. What fraction of the original atoms in a sample will remain after 21 years?
Date posted:
December 11, 2017
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Answers (1)
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A radioactive substance activity, initially at 400 counts per seconds reduces to 50 counts per second in 72 minutes. Determine the half-life of the substances.
(Solved)
A radioactive substance activity, initially at 400 counts per seconds reduces to 50 counts per second in 72 minutes. Determine the half-life of the substances.
Date posted:
December 11, 2017
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Answers (1)
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Give one reason why a- particles are more ionizing than ß-particles.
(Solved)
Give one reason why α- particles are more ionizing than β-particles.
Date posted:
December 11, 2017
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Answers (1)
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A radiation of wavelength 4.3 x 10^-7 m is shone on two different metal surface, nickel and potassium . (Speed of light 3.0 x10^8m/s, plank’s...
(Solved)
A radiation of wavelength 4.3 x 10^-7 m is shone on two different metal surface, nickel and potassium . (Speed of light 3.0 x10^8m/s, plank’s constant h as 6.63 x 10^-34 Js
i. Determine the energy of the incident radiation.
ii. If the work function of nickel is 8.0 x 10^-19J and that of potassium 3.68 x 10^-19J, which of the two metal will the given light eject electrons, state the reason.
iii. Calculate the velocity of the emitted electrons from the metal surface in (ii) above. (take the mass of an electron as 9.1 x 10^-31kg)
Date posted:
December 10, 2017
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Answers (1)
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The maximum wavelength required to make possible photoelectric emission on a metal surface is irradiated with light f frequency 8.5 x 10^14 Hz.
Determine:
i. The threshold frequency.
ii. The...
(Solved)
The maximum wavelength required to make possible photoelectric emission on a metal surface is irradiated with light f frequency 8.5 x 10^14 Hz.
Determine:
i. The threshold frequency.
ii. The work function of the metal in electron volts.
iii. The maximum kinetic energy f the electron.
Given that 1 eV = 1.6 x 10^-19J
Speed of light =3.0 x 10^8m/s
Plank’s constant h = 6.63 x 10^-34 Js
Date posted:
December 10, 2017
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Answers (1)
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What does the term work function mean?
(Solved)
What does the term work function mean?
Date posted:
December 10, 2017
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Answers (1)
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The work function of a certain material is 3.5 eV. Determine the threshold frequency for the material. (1 electron volt eV = 1.6 x...
(Solved)
The work function of a certain material is 3.5 eV. Determine the threshold frequency for the material. (1 electron volt eV = 1.6 x 10^-19 J, and plank’s constant h = 6.62 x10^-34 Js )
Date posted:
December 9, 2017
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Answers (1)
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The minimum frequency of radiation needed to cause photoelectric effect on a certain metal surface is 9.05 x 10^14 Hz. Determine the work...
(Solved)
The minimum frequency of radiation needed to cause photoelectric effect on a certain metal surface is 9.05 x 10^14 Hz. Determine the work function of the metal. (Plank’s constant h=6.63 x 10^-34 Js).
Date posted:
December 9, 2017
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Answers (1)
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How many milligram in one kilogram?
(Solved)
How many milligram in one kilogram?
Date posted:
December 9, 2017
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Answers (1)
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State the advantages of lead acid accumulator over primary cell
(Solved)
Advantages of lead acid accumulator over primary cell
Date posted:
December 9, 2017
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Answers (1)
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Give the applications of reflection of sound
(Solved)
Give the applications of reflection of sound.
Date posted:
December 9, 2017
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Answers (1)
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The surface of a metal was struck by a light of certain wavelength. State what determine the maximum kinetic energy of the electron emitted.
(Solved)
The surface of a metal was struck by a light of certain wavelength. State what determine the maximum kinetic energy of the electron emitted.
Date posted:
December 7, 2017
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Answers (1)
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Calculate the photon energy in ultra violet radiation whose frequency is 8.70 x 10^14 Hz. (Plank’s constant, h = 6.63 x 10^-34Js)
(Solved)
Calculate the photon energy in ultra violet radiation whose frequency is 8.70 x 10^14 Hz. (Plank’s constant, h = 6.63 x 10^-34Js)
Date posted:
December 7, 2017
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Answers (1)
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State common systems of unit as used in environmental soil physics
(Solved)
State common systems of unit as used in environmental soil physics.
Date posted:
December 7, 2017
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Answers (1)