- Hydrogen gas bubbles seen at the cathode
- White deposit forms at the plates
- Relative density of the electrolyte drops
Kavungya answered the question on May 31, 2019 at 10:28
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Calculate the maximum speed at which the car can go round the bend without skidding if the coefficient of friction between the tyres and the...
(Solved)
Calculate the maximum speed at which the car can go round the bend without skidding if the coefficient of friction between the tyres and the ground is 0.5.
Date posted:
May 31, 2019
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Answers (1)
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A 50W heating coil is totally immersed in 100g of water contained in an insulated flask of negligible heat capacity. The initial temperature of water...
(Solved)
A 50W heating coil is totally immersed in 100g of water contained in an insulated flask of negligible heat capacity. The initial temperature of water in the flask is 20oc.
i) Determine how long it takes for the water to boil at 100oC when the heater is switched on
ii) After the water has been boiling for 15 minutes, it is found that the mass of water in the flask has decreased to 80g. Assuming no external heat losses, calculate a value for the specific latent heat of vaporization of water
Date posted:
May 31, 2019
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Answers (1)
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A hole of area 2.0cm2 at the bottom of a tank 5m deep is closed with a cork. Determine the force on the cork when...
(Solved)
A hole of area 2.0cm2 at the bottom of a tank 5m deep is closed with a cork. Determine the force on the cork when the tank is filled with sea water of density 1.2g/cm3.
Date posted:
May 31, 2019
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Answers (1)
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An electric kettle with a 2.0kw heating element has a heat capacity of 400j/k. 1.0kg of water at 20°C is placed in the kettle. The...
(Solved)
An electric kettle with a 2.0kw heating element has a heat capacity of 400j/k. 1.0kg of water at 20°C is placed in the kettle. The kettle is switches on and it is found that 13 minutes later the mass of water in it is 0.5kg. Ignoring heat losses ; calculate
i) Total heat supplied.
ii) Heat used for the kettle.
iii) Heat used to raise temperature of 1kg of water from 20°C to 100°C.
iv) Heat to change water at 100°C to steam at 100°C.
v) The specific latent heat of vaporization of water.
Date posted:
May 31, 2019
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Answers (1)
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A car of mass 800g is initially moving at 25m/s. Calculate the force needed to bring the car to rest over a distance of 20m.
(Solved)
A car of mass 800g is initially moving at 25m/s. Calculate the force needed to bring the car to rest over a distance of 20m.
Date posted:
May 31, 2019
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Answers (1)
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In an experiment to determine the thickness of an oil molecule, an oil drop of volume 3.60 x 10-6 m3 was observed to form a...
(Solved)
In an experiment to determine the thickness of an oil molecule, an oil drop of volume 3.60 x 10-6 m3 was observed to form a circular patch of diameter 0.016m on the surface of water covered with lycopodium powder
i). Explain why the oil drop forms a circular patch.
ii) Determine the thickness of the oil molecule
Date posted:
May 31, 2019
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Answers (1)
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The figure below shows a uniform plank AB of length 10m weighing 500N. Two masses measuring 25kg and 60kg are loaded on its ends.
Determine the...
(Solved)
The figure below shows a uniform plank AB of length 10m weighing 500N. Two masses measuring 25kg and 60kg are loaded on its ends.
Determine the distance from point A where a support should be placed for the plank to balance horizontally.
Date posted:
May 31, 2019
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Answers (1)
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A small drop of oil has a volume of 5 × 10-8m³. When it is put on the surface of some clean water, it forms...
(Solved)
A small drop of oil has a volume of 5 × 10-8m³. When it is put on the surface of some clean water, it forms a circular film of 0.1m² in area; what is the size the a molecule oil.
Date posted:
May 31, 2019
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Answers (1)
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The distance between the ice point and steam point on a liquid in glass thermometer is 30cm. what temperature is recorded when the mercury thread...
(Solved)
The distance between the ice point and steam point on a liquid in glass thermometer is 30cm. what temperature is recorded when the mercury thread is 12cm above the ice point?
Date posted:
May 31, 2019
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Answers (1)
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A single spring stretches by 2.0 cm when supporting a load of 50N. If in the system below the springs are identical and have negligible...
(Solved)
A single spring stretches by 2.0 cm when supporting a load of 50N. If in the system below the springs are identical and have negligible weight
Find:
a) The total extension of the system.
b) The total spring constant.
Date posted:
May 31, 2019
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Answers (1)
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The diagram below shows a micrometer screw gauge used by a student to measure the thickness of a wire. If it has a zero error...
(Solved)
The diagram below shows a micrometer screw gauge used by a student to measure the thickness of a wire. If it has a zero error of 0.06mm, what is the actual thickness of the wire?
Date posted:
May 31, 2019
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Answers (1)
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A transformer is used to provide a potential difference of 100KV to an X-ray tube from 250V a.c mains supply. A current of 100mA flows...
(Solved)
A transformer is used to provide a potential difference of 100KV to an X-ray tube from 250V a.c mains supply. A current of 100mA flows in ht X-ray tube and the transformer is 100% efficient. Calculate:-
(i) The ratio of the number of turns of the secondary coil to the number of turns in the primary coil.
(ii) The current in the primary coil.
(iii) State giving reasons which of the coils of the transformer is thinner.
Date posted:
May 31, 2019
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Answers (1)
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In an experiment to determine the refractive index of a liquid, the liquid was poured into a measuring cylinder, a pin was
placed at the bottom...
(Solved)
In an experiment to determine the refractive index of a liquid, the liquid was poured into a measuring cylinder, a pin was
placed at the bottom of the cylinder and another pin was used to locate the apparent position of the first pin. The values
of real and apparent depth were used to plot a graph in the figure below.
i) From the graph determine the refractive index of the liquid.
ii) Given that the velocity of light in vacuum is 3.0 x 108 m/s what would be the velocity of light in the liquid
above.
Date posted:
May 31, 2019
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Answers (1)
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The coil of an electric motor is usually wound on a soft iron armature. State two purposes of this armature.
(Solved)
The coil of an electric motor is usually wound on a soft iron armature. State two purposes of this armature.
Date posted:
May 31, 2019
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Answers (1)
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A 200g mass of copper was heated to 100°C and then transferred to a lagged copper calorimeter of mass 5g containing 125g of water at...
(Solved)
A 200g mass of copper was heated to 100°C and then transferred to a lagged copper calorimeter of mass 5g containing 125g of water at 30°C. Calculate the final temperature of water. (Specific heat capacity of copper = 400J/KgK, water =4200J/KgK).
Date posted:
May 31, 2019
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Answers (1)
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The expression below is an equation for a radioactive element P. Element Q and R are the daughter nuclides. P, Q and R are not...
(Solved)
The expression below is an equation for a radioactive element P. Element Q and R are the daughter nuclides. P, Q and R are not the actual symbols of any of the elements.
Identify the element R and state two of its characteristics.
Date posted:
May 31, 2019
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Answers (1)
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The mass of the fabric of a large balloon is 100kg. The balloon is inflated with 200cm3 of helium. The balloon is attached to a...
(Solved)
The mass of the fabric of a large balloon is 100kg. The balloon is inflated with 200cm3 of helium. The balloon is attached to a cable fixed to the ground as shown.
(Density of air and helium are 1.25kg/m3 and 0.2kg/m3 respectively)
i) Indicate all the forces acting on the system.
ii) If the system is at equilibrium, write an equation relating the three forces in (i) above.
iii) Calculate the upthrust on the balloon.
Date posted:
May 31, 2019
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Answers (1)
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A motorcycle is travelling at a constant speed of 72km/h around a circular track of radius 150m.
i) Determine its centripetal acceleration.
ii) How long does...
(Solved)
A motorcycle is travelling at a constant speed of 72km/h around a circular track of radius 150m.
i) Determine its centripetal acceleration.
ii) How long does the cyclist take to complete one full cycle of the track?
Date posted:
May 31, 2019
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Answers (1)
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A column of glycerine 8.20m high, a column of sea water 10.08m high, column of mercury 0.76m high and a column of fresh water 10.34m...
(Solved)
A column of glycerine 8.20m high, a column of sea water 10.08m high, column of mercury 0.76m high and a column of fresh water 10.34m high exert the same pressure at the bottom of the container.Given that the pressure exerted by a fluid is given by P = h g, arrange these liquid in decreasing order of their densities.
Date posted:
May 31, 2019
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Answers (1)
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5 images are formed when two mirrors are inclined at an angle between them. Determine the angle of inclination.
(Solved)
5 images are formed when two mirrors are inclined at an angle between them. Determine the angle of inclination.
Date posted:
May 31, 2019
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Answers (1)