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impurities weaken/break the thin elastic skin hence lowering surface tension force
mwandavee answered the question on November 3, 2017 at 15:48
- (a) What is meant by specific latent heat of fusion of a substance? (b) In an experiment to determine the specific latent heat of vaporization...(Solved)
(a) What is meant by specific latent heat of fusion of a substance?
(b) In an experiment to determine the specific latent heat of vaporization of water, steam at 100ºC was passed into water
contained in a well-lagged copper calorimeter. The following measurements were made:
? Mass of calorimeter = 60g
? mass of water + calorimeter = 145g
? Final mass of calorimeter + water + condensed steam = 156g
? Final temperature of the mixture = 48oC
[Specific heat capacity of water = 4200JKg¯¹k¯¹ and specific heat capacity of copper = 390JKg¯¹k¯¹]
Determine the;
(i) mass of condensed steam.
(ii) The heat gained by the water and calorimeter if the initial temperature of the calorimeter and water is 20ºC.
(iii) Given that Lvis the specific latent heat of vaporization of steam, write an expression for the heat given out by steam.
(iv) Determine the value of Lv above (2marks)
(v) State the assumption made in the above experiment
Date posted: November 2, 2017. Answers (1)
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strikes a wooden block of wood of mass 976g
resting...(Solved)
A bullet of mass 24g travelling in a horizontal path with a velocity of 450ms-1
strikes a wooden block of wood of mass 976g
resting on a rough horizontal surface. After impact, the bullet and the block move together for a distance of 7.5m before
coming rest.
(a) Name the type of collision which takes place above (1 mark)
(b) What‘s the velocity of the two bodies when they start sliding (2 marks)
(c) Calculate the force which brings the two bodies to rest (3 marks)
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Date posted: November 2, 2017. Answers (1)
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In an experiment to determine the specific latent heat of vaporization of water, steam of mass 20g at 100⁰C is passed into 200g of water initially at 40⁰C in a container of negligible heat capacity. The temperature of the water rises to 80⁰C. (take the specific capacity of water 4200J/kg/k and the boiling water as 100⁰C)
i. Determine the specific latent heat of vaporization of water.
ii. What are the two errors in this experiment?
Date posted: November 2, 2017. Answers (1)
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Bubbles are seen to rise to the surface when the temperature of water reaches it boiling point.
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Date posted: November 2, 2017. Answers (1)
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