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1. Intrinsic semiconductors are pure materials which conduct electricity under suitable conditions like increase in temperature.
2. Extrinsic semiconductors are materials that have been fitted with impurities
sharon kalunda answered the question on March 25, 2019 at 13:40
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A doctor suspects that one of the kidneys of a patient is not working properly. The doctor injects him with a radioactive impurity, 1MBq of iodine-131 (half-life 8 days) which travels to his kidneys. A normal kidney gradually removes all impurity from the blood in about 20 minutes. The radioactivity in his kidney is monitored. using gamma ray detectors. The graph below shows the results.
a) Which kidney do you think is not working properly? Explain your answer.
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Date posted: March 25, 2019. Answers (1)
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Date posted: March 25, 2019. Answers (1)
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i) What happens the leaf of electroscope.
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Date posted: March 25, 2019. Answers (1)
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In the horizontal space provided, sketch the cylinders in neutral equilibrium
Date posted: March 25, 2019. Answers (1)
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Date posted: March 25, 2019. Answers (1)
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Date posted: March 25, 2019. Answers (1)
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Date posted: March 25, 2019. Answers (1)
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Determine the weight W that just holds the bar in the horizontal position shown.(Solved)
The figure shows a device for closing a steam outlet
The area of the piston is 4.0 x 10-4 m2 and the pressure of the steam in the boiler
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Date posted: March 25, 2019. Answers (1)
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Date posted: March 25, 2019. Answers (1)
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The figure below shows an arrangement for lighting three lamps, A, B and C only one of which is controlled directly by the switch.
a) Which of he lamp is directly controlled by the switch?
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c) Which lamps can be on at once?
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Date posted: March 25, 2019. Answers (1)
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Date posted: March 25, 2019. Answers (1)
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Date posted: March 25, 2019. Answers (1)