It gains and loses magnetism easily. It is only magnetized if there is a magnetic field around it and looses its magnetism immediately the field is withdrawn. It also requires very little energy to magnetize and demagnetize.
johnmulu answered the question on February 11, 2017 at 05:09
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State two factors that affect the strength of an electromagnet
(Solved)
State two factors that affect the strength of an electromagnet.
Date posted:
February 11, 2017
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Answers (1)
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The force on a conductor carrying current in a magnetic field can be varied by changing among others, the magnitude of the current and the magnetic field strength
(Solved)
The force on a conductor carrying current in a magnetic field can be varied by changing among others, the magnitude of the current and the magnetic field strength. Name two other factors that can be changed to vary the force
Date posted:
February 9, 2017
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Answers (1)
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State one application of each the following.
(i) Convex mirror
(ii) Parabolic mirror
(iii) Concave mirrors
(Solved)
State one application of each the following.
i) Convex mirror
ii) Parabolic mirror
(iii) Concave mirrors
Date posted:
February 7, 2017
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Answers (1)
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A lady holds a large concave of focal length 1 m, 80 cm from her face. State two characteristics of her image in the mirror
(Solved)
A lady holds a large concave of focal length 1 m, 80 cm from her face. State two characteristics of her image in the mirror
Date posted:
February 7, 2017
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Answers (1)
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A person carrying a heavy luggage using one hand leans away from the luggage. State the reason for this
(Solved)
A person carrying a heavy luggage using one hand leans away from the luggage. State the reason for this.
Date posted:
February 7, 2017
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Answers (1)
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State the reason why a steel sphere resting on a horizontal surface is said to be in neutral equilibrium
(Solved)
State the reason why a steel sphere resting on a horizontal surface is said to be in neutral equilibrium
Date posted:
February 7, 2017
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Answers (1)
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A uniform metal strip is 3.0 cm wide, 0.6 cm thick and d 100 cm long. The density of the metal is 2.7 g/cm3
(Solved)
A uniform metal strip is 3.0 cm wide, 0.6 cm thick and d 100 cm long. The density of the metal is 2.7 g/cm3. Determine the weight of the strip
Date posted:
February 7, 2017
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Answers (1)
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State the principle of moments
(Solved)
State the principle of moments
Date posted:
February 7, 2017
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Answers (1)
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State how the position of the centre of gravity of a body in stable equilibrium changes to that in the rest position when the body
(Solved)
State how the position of the centre of gravity of a body in stable equilibrium changes to that in the rest position when the body is slightly tilted and then released
Date posted:
February 7, 2017
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Answers (1)
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State two factors that should be controlled in manufacturing a cylindrical container of uniform thickness, which should normally be in a standing position?
(Solved)
State two factors that should be controlled in manufacturing a cylindrical container of uniform thickness, which should normally be in a standing position?
Date posted:
February 7, 2017
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Answers (1)
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What is meant by the centre of gravity of a body
(Solved)
What is meant by the centre of gravity of a body
Date posted:
February 7, 2017
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Answers (1)
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State factors that affects the turning effect of a force on a body
(Solved)
State factors that affects the turning effect of a force on a body.
Date posted:
February 7, 2017
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Answers (1)
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The moment of the weight of vertical door does not significantly affect the moment of the force required to open the door
(Solved)
The moment of the weight of vertical door does not significantly affect the moment of the force required to open the door. Give a reason for this.
Date posted:
February 7, 2017
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Answers (1)
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When a drop of organic 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 organic 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 the acid is estimated by determining the area of the patch
Date posted:
February 7, 2017
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Answers (1)
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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
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Answers (1)
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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
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Answers (1)
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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
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Answers (1)
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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
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Answers (1)
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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
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Answers (1)
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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
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Answers (1)