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(i) As the diaphragm vibrates, it causes the coil to move back and forth in the magnetic field cutting the field lines. This causes a varying electro-magnetic force to be induced in the coil which causes a varying current to flow.
(ii) - Increasing number of turns in the coil
- Increasing the strength of the magnet
johnmulu answered the question on June 5, 2017 at 11:39
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Date posted: June 5, 2017. Answers (1)
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Date posted: June 5, 2017. Answers (1)
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Date posted: June 5, 2017. Answers (1)
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Date posted: June 5, 2017. Answers (1)
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Date posted: June 5, 2017. Answers (1)
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(i) State what is observed on the spring balance and the weighing balance, as the metal block is gradually lowered into the water.
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(II) Observation on weighing balance
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Date posted: June 5, 2017. Answers (1)
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Figure 13 shows a log of wood of mass 20 kg submerged in water in a pond and held in position by a string fixed to the bottom of the pond.
Given that the density of water is 1000 kgm -3 and that of wood is 800 kgm -3, determine the;
(i) Volume of the log.
(ii) Upthrust of the log.
(iii) Tension in the string.
Date posted: June 5, 2017. Answers (1)
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Figure 18 shows parts of a simple submarine, a ship that can travel both on water and under water. To do this water is pumped in or out of the ballast tanks.
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Date posted: June 5, 2017. Answers (1)
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Determine the;
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(b) upthrust on the stone;
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Date posted: June 5, 2017. Answers (1)
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Figure 10 shows a rectangular metal block of density 10500 kgm-3 and dimensions 30 cm x 20 cm x 20 cm suspended inside a liquid of density 1200 kgm-3 by a string attached to a point above the liquid. The three forces acting on the block are the tension T, On the string, the weight W, of the block and the upthrust, U due to the liquid.
(i) Write the expression relating T, W and U when the block is in equilibrium inside the liquid.
(ii) Determine the weight, W of the block.
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Date posted: June 5, 2017. Answers (1)
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Date posted: June 5, 2017. Answers (1)
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Date posted: June 5, 2017. Answers (1)
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(i) State the purpose of the lead shots in the glass bulb.
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Date posted: June 5, 2017. Answers (1)