The rotation of the ball in anticlockwise direction interfere with lamina air flow in such a way that air flow over the ball is faster that air flow below and the consecutive result in reduced pressure over the ball causes lift which makes the ball move up.
Mr Gatheru answered the question on September 17, 2017 at 10:55
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(Solved)
Distinguish between solid and liquid using molecular motion
Date posted: September 16, 2017. Answers (1)
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Explain how the braking system of a car works.
Date posted: September 15, 2017. Answers (1)
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Date posted: September 15, 2017. Answers (1)
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Date posted: September 15, 2017. Answers (1)
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Date posted: September 15, 2017. Answers (1)
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Date posted: September 12, 2017. Answers (1)
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Date posted: June 8, 2017. Answers (1)
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Figure 8 shows a uniform light bar resting horizontally on corks floating on water in two beakers A and B.
Explain why the bar tilts towards side A when equal amount of heat is supplied to each beaker.
Date posted: June 7, 2017. Answers (1)
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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. Answers (1)
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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. Answers (1)
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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. Answers (1)
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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).
State the reason for this observation.
Date posted: June 7, 2017. Answers (1)
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Figure 5 shows the circuit of a rectifier using four diodes D1, D2, D3 and D4.
Explain how a rectified output is produced from the set up when an a.c input is connected across AB.
Date posted: June 6, 2017. Answers (1)
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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. Answers (1)
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The following is part of a radioctive decay series.
Determine the values of a and b.
Date posted: June 6, 2017. 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:
Determine the values of:
(a) x (b) y
Date posted: June 6, 2017. Answers (1)
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The equation below represents a nuclear reaction in which two deuterium nuclei fuse to form Helium and X.
(a) Determine the values of a and b.
(b) Identify X
Date posted: June 6, 2017. Answers (1)
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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. 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.
(i) Determine the values of 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. Answers (1)