Let red pens be r.
blue pens is 38 - r
Thus
6r + 4(38 - r) = 192
6r + 152 - 4r = 192
2r = 40, r = 20
red pens = 20,
blue pens = 18.
johnmulu answered the question on June 8, 2017 at 12:26
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Figure 8 shows a uniform light bar resting horizontally on corks floating on water in two beakers A and B.
(Solved)
Figure 8 shows a uniform light bar resting horizontally on corks floating on water in two beakers A and B.
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Date posted:
June 7, 2017
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Answers (1)
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(Solved)
The light uniform bar in Figure 3 is in equilibrium. The two beakers A and B contain water at the same temperature. The two blocks are made of the same material.
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Date posted:
June 7, 2017
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Answers (1)
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Figure 11 shows a depletion layer in an unbiased p-n junction.
(Solved)
Figure 11 shows a depletion layer in an unbiased p-n junction.
State how a battery can be used to make the depletion layer narrower.
Date posted:
June 7, 2017
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Answers (1)
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Figure 12 shows a depletion layer in an unbiased p-n junction.
(Solved)
Figure 12 shows a depletion layer in an unbiased p-n junction.
State how a battery can be used to make the depletion layer narrower.
Date posted:
June 7, 2017
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Answers (1)
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(Solved)
Figure 6 (a) and Figure 6 (b) show a p-n junction connected to a battery. It is observed that the current in figure (6) (a) is greater than the current in figure 6 (b).
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Date posted:
June 7, 2017
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Answers (1)
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Figure 5 shows the circuit of a rectifier using four diodes D1, D2, D3 and D4.
(Solved)
Figure 5 shows the circuit of a rectifier using four diodes D1, D2, D3 and D4.
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Date posted:
June 6, 2017
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Answers (1)
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(Solved)
In the circuit in fig. 5, when the switch S is closed, the voltmeter shows a reading.
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Date posted:
June 6, 2017
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Answers (1)
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The following is part of a radioctive decay series.
(Solved)
The following is part of a radioctive decay series.
Determine the values of a and b.
Date posted:
June 6, 2017
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Answers (1)
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Radium undergoes radioctive decay by emitting an alpha particle to form a daughter nuclide Q as in the reaction:
(Solved)
Radium undergoes radioctive decay by emitting an alpha particle to form a daughter nuclide Q as in the reaction:
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Date posted:
June 6, 2017
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Answers (1)
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(Solved)
The equation below represents a nuclear reaction in which two deuterium nuclei fuse to form Helium and X.
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Date posted:
June 6, 2017
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Answers (1)
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(Solved)
Figure 6, shows a narrow beam of radiation from a radioctive source, incident to a postcard. The emergent radiation passes through a magnetic field which perpendicular to the plane of the paper, and into the paper.
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Date posted:
June 6, 2017
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Answers (1)
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The following is a nuclear equation for a fission process resulting from the reaction of a neutron with a Uranium nucleus.
(Solved)
The following is a nuclear equation for a fission process resulting from the reaction of a neutron with a Uranium nucleus.
(i) Determine the values of of x and y
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(iii) Explain how this reaction is made continuous in a nuclear reactor
Date posted:
June 6, 2017
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Answers (1)
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Figure 11 shows the path of radiation from a radioactive source. The field is perpendicular to the paper and directed out of the paper.
(Solved)
Figure 11 shows the path of radiation from a radioactive source. The field is perpendicular to the paper and directed out of the paper.
(a)Identify the radiation.
(b) (i) State the effect of the radiation on the gas inside the Geiger-Muller tube.
(ii) Explain how the large discharge current is created.
(c) The following is a nuclear equation for a fission process resulting from the reaction of a neutron with a Uranium nucleus.
(i) Determine the values of x and y.
ii) State the source of the energy released.
(iii)Explain how this reaction is made continuous in a nuclear reactor.
Date posted:
June 6, 2017
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Answers (1)
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A radioactive isotope of copper decays to form an isotope of Zinc as shown below.
(Solved)
A radioactive isotope of copper decays to form an isotope of Zinc as shown below.
Name the radiation emitted and give a reason for your answer.
Date posted:
June 6, 2017
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Answers (1)
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A nuclear reaction is represented by the following equation.
(Solved)
A nuclear reaction is represented by the following equation.
Determine the values of a and b
Date posted:
June 6, 2017
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Answers (1)
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The following represents a nuclear reaction involving the nuclide polonium Po.
(Solved)
The following represents a nuclear reaction involving the nuclide polonium Po.
Identify m, n and X
Date posted:
June 6, 2017
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Answers (1)
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Figure 4 shows the cross-section of a diffusion cloud chamber used to detect radiation from radioctive sources.
(Solved)
Figure 4 shows the cross-section of a diffusion cloud chamber used to detect radiation from radioctive sources.
(i) State one function of each of the following:
Alcohol
Solid CO2
(ii) When radiation from the source enters the chamber, some white traces are observed. Explain how these traces are formed and state how the radiation is identified.
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Date posted:
June 6, 2017
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Answers (1)
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Figure 4 shows a Geiger Muller (G.M,) tube.
(Solved)
Figure 4 shows a Geiger Muller (G.M,) tube.
(i) Give the reason why the mica window is made thin
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(iii) What is the purpose of the halogen vapour?
Date posted:
June 6, 2017
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Answers (1)
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The following equation shows part of a radioactive decay process.
(Solved)
The following equation shows part of a radioactive decay process.
Name the radiation x
Date posted:
June 6, 2017
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Answers (1)
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Figure 3 shows a device for producing metal foils of constant thickness.
(Solved)
Figure 3 shows a device for producing metal foils of constant thickness. Any change in thickness can be detected by the Geiger tube and recorded by the Geiger counter. The pressure exerted by the roller is then adjusted to keep the thickness constant.
(i) State the change in the metal foil that will lead to a decrease in the Geiger counter reading.
(ii) Give a reason for your answer in (i) above.
(iii) State the change in the roller pressure that should be made as a result of this decrease in the Geiger counter reading.
(vi) Give a reason for answer in (iii) above.
Date posted:
June 6, 2017
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Answers (1)