(i) On rubbing the surface, electrons are transferred from the shoe to the nylon fibre.
This leaves the rubber shoes with a net positive charge.
joseph rimiru answered the question on January 6, 2018 at 19:44
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(a) What is diffusion?
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(c) A beaker is filled completely with water. A spoon full of common salt is added slowly. The salt dissolves and the water does not overflow.
(i) Why is salt added slowly?
(ii) Why doesn't the water overflow?
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(i) How much energy is given out by the bulb in 1second
(ii) Why is the wire coiled?
(iii) State two properties of tungsten which make it suitable for use in electric bulbs.
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(a) Explain what is meant by the terms longitudinal and transverse.
longitudinal
transverse
(b) State another example of a longitudinal wave, a transverse wave.
Date posted: January 2, 2018. Answers (1)
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(a) State the Archimedes principle (1mark)
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(i) The density of the wooden block (3 marks)
(ii) The volume of the wooden block remaining above the surface when floating in a liquid of density 900kg/m^3. (3 marks)
(iii) Additional weight required to be placed on the wooden block so as to just submerge in this liquid
(3 marks)
(c) A meteorological weather balloon of volume 1.2m^3 is tied to a rigid support while being filled with helium gas. The mass of the fabric making the weather balloon is 0.3kg.Determine the maximum tension on the string tying the balloon to the rigid support.(density of air = 1.25kg/m^3 and density of helium is 0.18kg/m^3) (4 marks)
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A syringe contains 100 cm^3 of air at atmospheric pressure. The atmospheric pressure is 1.0 × 10^5 Pascal. The open end of the syringe is sealed and the piston is pushed inwards until the air occupies a volume of 40 cm^3.The temperature of the air remains constant. Calculate the new pressure of the air in the syringe.
Date posted: January 1, 2018. Answers (1)