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Drop spreads out until the patch is one molecule thick
johnmulu answered the question on February 9, 2017 at 10:04
- Derive an expression for obtaining the diameter, d of a molecule of oil(Solved)
An oil drop of volume V m3 introduced on the surface of water spreads to form patch whose area is Am2. Derive an expression for obtaining the diameter, d of a molecule of oil.
Date posted: February 7, 2017. Answers (1)
- State two environmental hazards that may occur when oil spills over a large surface area of the sea(Solved)
State two environmental hazards that may occur when oil spills over a large surface area of the sea.
Date posted: February 7, 2017. Answers (1)
- When a drop of oleic acid of known volume is dropped on the surface of water in a large trough, it spreads out to form a large circular patch(Solved)
When a drop of oleic acid of known volume is dropped on the surface of water in a large trough, it spreads out to form a large circular patch. State one assumption made when the size of the molecule of oleic acid is estimated by determining the area of the patch.
Date posted: February 7, 2017. Answers (1)
- In an experiment to estimate the diameter of an oil molecule, an oil drop of diameter 0.05 cm spreads over a circular patch whose diameter is 20 cm(Solved)
In an experiment to estimate the diameter of an oil molecule, an oil drop of diameter 0.05 cm spreads over a circular patch whose diameter is 20 cm.
Determine i) the volume of the oil drop
ii) The area of the patch covered by the oil
iii) The diameter of the oil molecule
Date posted: February 7, 2017. Answers (1)
- State the assumption made when calculating the size of a molecule in the oil drop experiment(Solved)
State the assumption made when calculating the size of a molecule in the oil drop experiment
Date posted: February 7, 2017. Answers (1)
- Name the instrument that would be most suitable for measuring the thickness of one sheet of this question paper.(Solved)
Name the instrument that would be most suitable for measuring the thickness of one sheet of this question paper.
Date posted: February 7, 2017. Answers (1)
- State the reason why the magnetic field strength of a magnet is greatest at the poles(Solved)
State the reason why the magnetic field strength of a magnet is greatest at the poles.
Date posted: February 7, 2017. Answers (1)
- One method of producing a weak magnet is to hold a steel rod in the North South direction and the hammer is continuously for some time(Solved)
One method of producing a weak magnet is to hold a steel rod in the North South direction and the hammer is continuously for some time. Using the domain theory of magnetism explain how this method works.
Date posted: February 7, 2017. Answers (1)
- An un-magnetized steel rod is clamped facing North-South direction and then hammered repeatedly for some time. When tested, it is found to be magnetized(Solved)
An un-magnetized steel rod is clamped facing North-South direction and then hammered repeatedly for some time. When tested, it is found to be magnetized. Explain this observation
Date posted: February 7, 2017. Answers (1)
- How can it be shown that the strength of a magnet is concentrated at the poles(Solved)
How can it be shown that the strength of a magnet is concentrated at the poles
Date posted: February 7, 2017. Answers (1)
- Explain how hammering demagnetizes a magnet(Solved)
Explain how hammering demagnetizes a magnet
Date posted: February 7, 2017. Answers (1)
- Distinguish between soft and hard magnetic materials(Solved)
Distinguish between soft and hard magnetic materials
Date posted: February 7, 2017. Answers (1)
- Given a bar magnet, an iron bar and a string
i) Describe a simple experiment to distinguish between the magnet and the iron bar
(ii) State...(Solved)
Given a bar magnet, an iron bar and a string
i) Describe a simple experiment to distinguish between the magnet and the iron bar
(ii) State with reasons the observations that would be made in the experiment.
Date posted: February 7, 2017. Answers (1)
- Give reason why attraction in magnetism is not regarded as reliable method of testing for polarity(Solved)
Give reason why attraction in magnetism is not regarded as reliable method of testing for polarity
Date posted: February 7, 2017. Answers (1)
- State the reason for topping up a lead-acid accumulator with distilled water(Solved)
State the reason for topping up a lead-acid accumulator with distilled water.
Date posted: February 7, 2017. Answers (1)
- State the purpose of manganese dioxide in a dry cell(Solved)
State the purpose of manganese dioxide in a dry cell.
Date posted: February 7, 2017. Answers (1)
- State one advantage of a lead-acid accumulator over a nickel-iron(NiFe) accumulator(Solved)
State one advantage of a lead-acid accumulator over a nickel-iron(NiFe) accumulator.
Date posted: February 7, 2017. Answers (1)
- Explain how polarization reduces current in a simple cell(Solved)
Explain how polarization reduces current in a simple cell
Date posted: February 7, 2017. Answers (1)
- State one advantage of alkaline accumulator over a lead-acid accumulator(Solved)
State one advantage of alkaline accumulator over a lead-acid accumulator
Date posted: February 7, 2017. Answers (1)
- A car battery requires topping up with distilled water occasionally. Explain why this is necessary and why distilled water is used(Solved)
A car battery requires topping up with distilled water occasionally. Explain why this is necessary and why distilled water is used
Date posted: February 7, 2017. Answers (1)