The number of electrons reaching the screen (that determine the brightness of the beam) is controlled by making the grid less negative or more negative.
johnmulu answered the question on February 20, 2017 at 05:54
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a) State two factors that determine the resistance of metallic conductor.
b) Explain how a fuse safeguards electrical appliances against excessive currents.
c) A hair dryer is rated 2.5kW, 240 V.
i) Determine whether a 10 A fuse may be suitable for the hair dryer
ii) Determine the cost of using the dryer for 3 hours if the cost of electricity is Ksh. 0.80 per kilowatt hour.
Date posted: February 20, 2017. Answers (1)
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Date posted: February 20, 2017. Answers (1)
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A house has one 100 W bulb, two 60 W bulbs and one 30 W bulb. Determine the cost of having all the bulbs switched on for 70 hours, given that the cost of electricity is 40 cents per kilowatt hour.
(Solved)
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Date posted: February 20, 2017. Answers (1)
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Date posted: February 20, 2017. Answers (1)
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(i) The secondary voltage
(ii) The primary voltage;
Date posted: February 20, 2017. Answers (1)
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State what is meant by the term “electromagnetic induction”.
Date posted: February 20, 2017. Answers (1)
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Date posted: February 20, 2017. Answers (1)
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Date posted: February 20, 2017. Answers (1)
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Date posted: February 18, 2017. Answers (1)
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Date posted: February 18, 2017. Answers (1)