Topping:- The addition of distilled water into a lead acid accumulator to improve on the ion
concentration.
Dopping:- Addition of impurities to an intrinsic semiconductors to improve on its conductivity.
sharon kalunda answered the question on April 5, 2019 at 11:03
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Explain why eight 1.5V cells arranged in series to give a total of 12V cannot be used to start
a car. But car battery of 12V...
(Solved)
Explain why eight 1.5V cells arranged in series to give a total of 12V cannot be used to start
a car. But car battery of 12V starts a car
Date posted:
April 5, 2019
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Answers (1)
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Explain how conductivity of a semiconductor changes with increase in temperature
(Solved)
Explain how conductivity of a semiconductor changes with increase in temperature
Date posted:
April 5, 2019
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Answers (1)
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The diagram below shows a simple cell:-
(Solved)
The diagram below shows a simple cell:-
(i) Name z and solution y
(ii) Name and explain the defect that occurs at plate z
(iii) Give one method of preventing the defect that occurs at the copper plate
Date posted:
April 5, 2019
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Answers (1)
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The diagram below shows a wrongly wired three pin plug.
(Solved)
The diagram below shows a wrongly wired three pin plug.
(i) Indicate in the diagram above the correct colors for the wiring
(ii) State the use of device marked X
Date posted:
April 5, 2019
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Answers (1)
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The figure below represents part of an electric cooker coil.
(Solved)
The figure below represents part of an electric cooker coil.
i) State why the part labeled W is coiled
(ii) State the property of material X that makes it suitable for its use
Date posted:
April 5, 2019
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Answers (1)
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The diagram below represents a cathode ray oscilloscope (CRO)
(Solved)
The diagram below represents a cathode ray oscilloscope (CRO)
i) Name the parts labeled A and B
ii) What are the functions of C and D?
iii) State how electrons are produced
iv) Give a reason why the tube is evacuated.
Date posted:
April 5, 2019
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Answers (1)
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State one reason why a C.R.O is a more accurate voltmeter than a moving coil voltmeter
(Solved)
State one reason why a C.R.O is a more accurate voltmeter than a moving coil voltmeter
Date posted:
April 5, 2019
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Answers (1)
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An electric kettle is rated 3KW, 250V. Determine the resistance of the coil
(Solved)
An electric kettle is rated 3KW, 250V. Determine the resistance of the coil
Date posted:
April 5, 2019
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Answers (1)
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Given that a lamp is rated 45W 240V. Calculate the resistance of the heating element.
(Solved)
Given that a lamp is rated 45W 240V. Calculate the resistance of the heating element.
Date posted:
April 5, 2019
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Answers (1)
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What is the relationship between periodic time and frequency of a progressive wave?
(Solved)
What is the relationship between periodic time and frequency of a progressive wave?
Date posted:
April 5, 2019
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Answers (1)
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The figure below shows water waves crossing a boundary between deep and shallow water. Complete the diagram to show the wave in the deep region
(Solved)
The figure below shows water waves crossing a boundary between deep and shallow water
Complete the diagram to show the wave in the deep region.
Date posted:
April 5, 2019
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Answers (1)
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How many cubic centimeters make a gram?
(Solved)
How many cubic centimeters make a gram?
Date posted:
April 5, 2019
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Answers (1)
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The figure below shows two loudspeakers L1 and L2 connected to a signal generator.
(Solved)
The figure below shows two loudspeakers L1 and L2 connected to a signal generator.
An observer walks along the line 0-01 (equidistant from L1 and L2) and another along the
Line AA1.Explain the observation made by each and give reasons to your answer
Date posted:
April 5, 2019
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Answers (1)
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The diagram below represents plane wave fronts produced in a ripple tank.
(Solved)
The diagram below represents plane wave fronts produced in a ripple tank.
Given that the distance AB is 15 cm, determine the wavelength of the wave
Date posted:
April 5, 2019
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Answers (1)
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Calculate the pressure of the gas supply (Atmospheric pressure = 1.0x105Pa)
(Solved)
Calculate the pressure of the gas supply (Atmospheric pressure = 1.0x105Pa)
Date posted:
April 5, 2019
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Answers (1)
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Water of mass 200g at temperature of 60°Cis put in a well lagged copper calorimeter of mass
80g. A piece of ice at 0° C and...
(Solved)
Water of mass 200g at temperature of 60°Cis put in a well lagged copper calorimeter of mass
80g. A piece of ice at 0° C and mass 20g is placed in the calorimeter and the mixture stirred
gently until all the ice melts. The final temperature, T, of the mixture is then measured.
Determine:
i) The heat absorbed by the melting ice at O°C
ii) The heat absorbed by the melted ice (water) to rise to temperature T (answer may be
given in terms of T)
iii) The heat lost by the warm water and the calorimeter (answer may be given in terms of T)
iv) The final temperature of the mixture
Date posted:
April 5, 2019
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Answers (1)
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The figure below shows to light pith balls arranged as shown.
State what is observed when air is blown on the outer sides of the pith...
(Solved)
The figure below shows to light pith balls arranged as shown.
State what is observed when air is blown on the outer sides of the pith balls.
Date posted:
April 5, 2019
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Answers (1)
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A person’s lung pressure as recorded by a mercury manometer is 90 mm Hg. Express this
pressure in SI units.
(Solved)
A person’s lung pressure as recorded by a mercury manometer is 90 mm Hg. Express this
pressure in SI units.
Date posted:
April 5, 2019
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Answers (1)
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The graph below represents a graph of stopping potential Vs , V against frequency f, Hz
(Solved)
The graph below represents a graph of stopping potential Vs , V against frequency f, Hz
Use the graph to determine:
(i) The threshold frequency of the metal
(ii) Plank’s constant
(iii) Work function of the metal
Date posted:
April 5, 2019
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Answers (1)
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State and explain two features of a hydrometer that make it sensitive in its function
(Solved)
State and explain two features of a hydrometer that make it sensitive in its function
Date posted:
April 5, 2019
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Answers (1)