The speed of the electrons produced increase; hence the strength of x-rays is increased
joseph rimiru answered the question on January 3, 2018 at 15:50
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A metal iron has work function of 6.8 x 10^-19J. Calculate the minimum frequency of light that can cause photoelectric emission. (Take h = 6.63 x 10^-34 Js)
Date posted: January 2, 2018. Answers (1)
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Date posted: January 2, 2018. Answers (1)
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An electric bulb is rated ‘240V,100W .It contains a 1m long coiled tungsten wire . When switched on the wire reaches a temperature of about 2500 degrees Celsius.
(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.
Date posted: January 2, 2018. Answers (1)
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There are two types of seismic waves produced by earthquakes. They are called P-waves and S-waves. P-waves are longitudinal and S-waves are transverse.
(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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Date posted: January 2, 2018. Answers (1)
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Date posted: January 2, 2018. Answers (1)
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Date posted: January 2, 2018. Answers (1)
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Date posted: January 2, 2018. Answers (1)
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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)
Date posted: January 1, 2018. Answers (1)
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Date posted: January 1, 2018. Answers (1)
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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)
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Date posted: January 1, 2018. Answers (1)
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Date posted: December 29, 2017. Answers (1)
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Date posted: December 18, 2017. Answers (1)
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Date posted: December 14, 2017. Answers (1)
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Date posted: December 14, 2017. Answers (1)
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Date posted: December 14, 2017. Answers (1)
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Date posted: December 14, 2017. Answers (1)