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(i) (I) The reading of the spring balance decreases
(II) The reading on the weighing balance increases
(ii) This is due to upthrust acting on the metal block placed in water.
johnmulu answered the question on June 5, 2017 at 08:23
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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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Determine the;
(a) volume of the liquid displaced;
(b) upthrust on the stone;
(c) Reading of the spring balance;
Date posted: June 5, 2017. Answers (1)
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(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.
(iii) Determine the weight of the liquid displaced by the fully submerged block.
(iv) Hence determine the tension, T in the string.
Date posted: June 5, 2017. Answers (1)
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When temperature of the water is raised the system is observed to tilt to the right. State the reason for this observation.
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.
(ii) How would the hydrometer be made more sensitive?
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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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In an experiment to determine the density of a liquid, a uniform metal cylinder of cross-sectional area 6.2 cm2 and length 4.5 cm was hang from a spring balance and lowered gradually into the liquid. The upthrust was determined for various submerged lengths. The results obtained are shown on the graph in figure 1.
Using the graph, determine:
(i) The value of the upthrust when the cylinder is fully submerged.
(ii) The density of the liquid.
Date posted: June 5, 2017. Answers (1)
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Date posted: June 2, 2017. Answers (1)
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When water is added into the beakers A and B until the weights are submerged, it is observed that the bar tips towards B. Explain this observation.
Date posted: June 2, 2017. Answers (1)
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Figure 7 represents a block of uniform cross sectional area of 6.0 cm2 floating on two liquids A and B. The lengths of the block in each liquid are as shown.
Give that the density of liquid A is 800 kgm-3 and that of liquid B is 1000 kgm-3, determine the:
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Date posted: June 2, 2017. Answers (1)
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(i) Name two forces acting on the pendulum bob as it moves.
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(iii) State two applications of uniform circular motion in daily life.
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(i) State the purpose of banking roads at bends.
(ii) State a reason why the object is accelerating while its speed remains constant.
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d on the table before placing the masses. Explain the effect of this on the frequency at which each mass slides off.
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