i) When the oil drop is placed at the centre of tray, it spreads on the surface of the water until it is one molecule thick producing patch
ii) Put oil in a burette and read the level. Let 100 drops fall and then read the new level. Divide the difference in volume by the number of drops to obtain the volume of one drop.
johnmulu answered the question on April 18, 2017 at 09:39
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Date posted: April 18, 2017. Answers (1)
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Date posted: April 18, 2017. Answers (1)
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Date posted: April 18, 2017. Answers (1)
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Date posted: April 18, 2017. Answers (1)
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Explain the observation made when the switch is closed.
Date posted: April 18, 2017. Answers (1)
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Date posted: April 18, 2017. Answers (1)
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Date posted: April 18, 2017. Answers (1)
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Date posted: April 18, 2017. Answers (1)
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Using this information in Fig. 1 explain the difference between the substances P and Q with reference to the domain theory
Date posted: April 18, 2017. Answers (1)
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Date posted: April 18, 2017. Answers (1)
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i) Other than L1, state the lamp that will light when S1 and S2 are closed.
ii) How does the brightness in L1 in (i) above compare with its brightness when all the switches are closed?
iii) Explain the observation in (ii) above
Date posted: April 18, 2017. Answers (1)
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Date posted: April 18, 2017. Answers (1)
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a) Explain why the bulb in Figure 10 (b) will be brighter than each of the bulbs in Figure 10 (a).
b) Give the reason why the cells in Figure 10 (b) can be used for a longer period than the cells in Figure 10 (a).
Date posted: April 18, 2017. Answers (1)
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Figure 10 shows two circuits in which identical dry cells and identical bulbs are used. Use the information in the figure to answer questions a and b
a) Explain why the bulb in figure 10 (b) will be brighter than each of the bulbs in figure 10 (a).
b) Give the reason why the cells in figure 10 (b) can be used for a longer period than the cells in Figure (10a)
Date posted: April 17, 2017. Answers (1)
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State with reason, in which circuit the lamp will be lit for a longer period
Date posted: April 17, 2017. Answers (1)
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Date posted: April 17, 2017. Answers (1)
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State with a reason which one of the two thermometers shows a higher temperature
Date posted: April 17, 2017. Answers (1)
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Figure 4 shows a source of heat placed at equal distances from two identical flasks X and Y containing air. The surface of X is painted black while Y is clear.
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Date posted: April 17, 2017. Answers (1)
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Figure 3 shows a piece of wood fitted into copper pipe and a piece of a paper wrapped tightly around the junction.
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Date posted: April 17, 2017. Answers (1)
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Explain what happened to the ventilation when the fire was lit
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Date posted: April 17, 2017. Answers (1)