To control the number of electrons reaching the screen; control the brightness of the screen.
chrispohmomanyi answered the question on October 5, 2017 at 10:32
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State two uses of radioactivity in hospitals.
Date posted: October 5, 2017. Answers (1)
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Date posted: October 5, 2017. Answers (1)
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Date posted: October 5, 2017. Answers (1)
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Date posted: October 5, 2017. Answers (1)
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Date posted: October 5, 2017. Answers (1)
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Date posted: October 5, 2017. Answers (1)
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Date posted: October 5, 2017. Answers (1)
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Date posted: October 5, 2017. Answers (1)
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A tungsten filament lamp contains Argon gas at low pressure. Why is air not used?
Date posted: October 5, 2017. Answers (1)
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What is the difference between P-type and N-type semiconductors.
Date posted: October 5, 2017. Answers (1)
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Date posted: October 4, 2017. Answers (1)
- A scout blew a trumpet some distance from a wall, and heard its echo after 3.6 seconds later. How far is the wall from the...(Solved)
A scout blew a trumpet some distance from a wall, and heard its echo after 3.6 seconds later. How far is the wall from the scout? (speed of sound in air is 330 m/s)
Date posted: October 4, 2017. Answers (1)
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An insulated copper wire rolled on an iron core results to an electromagnet. State two changes that can increase the strength of the electromagnet.
Date posted: October 4, 2017. Answers (1)
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Date posted: October 4, 2017. Answers (1)
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Date posted: October 4, 2017. Answers (1)
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Date posted: October 4, 2017. Answers (1)
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State one property of electromagnetic waves.
Date posted: October 4, 2017. Answers (1)
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State the condition under which a converging lens is used as a magnifying glass.
Date posted: October 4, 2017. Answers (1)
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State two ways of increasing the size of the image in a pinhole camera.
Date posted: October 4, 2017. Answers (1)
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State the type of wave produced when a wire fixed at both ends is jerked.
Date posted: October 4, 2017. Answers (1)