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The barometric height in a town is 65cmHg. Given that the standard atmospheric pressure is 76cmHg and the density of mercy is 13600kg/m³, determine the attitude of the town. (Density of air is 1.25kg/m³).
Date posted:
June 3, 2019
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A burette has an initial reading of 22.5cm³. Determine the final reading after liquid of volume of 11.3cm³. To removal from the burette.
Date posted:
June 3, 2019
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Plane water wavefronts are incident onto a concave barrier as shown in the figure below.
Show on the same diagram the nature of the reflected wavefronts.
Date posted:
June 3, 2019
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A vibrator is used to generate water waves in a ripple tank. It is observed that the distance between the first crest and the mid-point to the fifth trough is 237.5cm.
The waves travel 224.0cm in 6.0 seconds.
Determine:
(i) the wavelength of the waves.
(ii) the speed of the waves.
(iii) the frequency of the vibrator.
Date posted:
June 3, 2019
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A sample of Iodine-131 contains 1000g. If the half-life of Iodine-131 is 8 days, how much of the sample will remain undecayed after 40 days?
Date posted:
June 3, 2019
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The figure below shows a thick copper conductor placed between two poles of a strong magnet. The wire is free to swing in between the poles.
(a) Indicate on the same diagram the direction in which the conductor swings when the switch K is closed.
(b) State one change that can be made on the set up so that the direction of swing of the conductor is reversed.
Date posted:
June 3, 2019
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A girl standing 120m away from a tall building claps her hands and hears an echo 0.75s later. Determine the speed of sound in air at this place.
Date posted:
June 3, 2019
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The figure below shows an incomplete circuit of an electromagnet.
Complete the circuit by drawing the windings on the two arms of the core so that A and B are both north poles when the switch S is closed. Indicate the direction of the current of the windings drawn.
Date posted:
June 3, 2019
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A current of 0.8A flows through an electric circuit. Determine the quantity of charge that passes a point in the circuit in 6 minutes.
Date posted:
June 3, 2019
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The figure below shows an iron cylinder of length 10cm and uniform cross-section 2cm² suspended
from a spring balance with half of its length immersed in paraffin oil of density 0.8gcmˉ³.
(i) Show on the diagram, the forces acting on the iron cylinder.
(ii) If the density of iron is 7.5gmˉ³ determine.
(i) the weight of the iron cylinder.
(ii) the reading of the spring balance.
Date posted:
June 3, 2019
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Draw a clear labeled diagram of a common hydrometer which is suitable for measuring the densities of liquid varying between 1.0 and 1.2 g/cm³.
Date posted:
June 3, 2019
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A trolley of height 0.2m moving on a horizontal bench of height 3.2m strikes a barrier at the edge of the bench. The object on top of the trolley flies off on impact and lands on the ground 2.5m from the edge of the bench as shown in the figure below.
Use this information to answer the questions that follow.
(i) Give a reason why the object on the trolley flies off on impact.
(ii) Determine the time taken by the object to reach the ground.
Date posted:
June 3, 2019
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A stone is thrown vertically upwards from an edge of a platform. Eventually the stone lands without bouncing, on the ground below the platform. Taking the upward velocity to be positive, sketch the velocity-time graph of the motion of the stone.
Date posted:
June 1, 2019
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The mercury column in a barometer is 760mm high. Taking the density of mercury to be 13.6g/cm³, calculate the atmospheric pressure in N/m².
Date posted:
June 1, 2019
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An object weighs 49N on earth where acceleration due to gravity is 9.8N/kg. Find the acceleration due to gravity on another planet where the same object weighs 40.5N.
Date posted:
June 1, 2019
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A string of negligible mass has a bucket tied at the end. The string is 60cm long and the buckets has a mass of 45g. The bucket is swung horizontally making 6 revolutions per second. Calculate:
(i) The angular velocity.
(ii) The centripetal acceleration.
(iii) The tension on the string.
(iv) The linear velocity.
Date posted:
June 1, 2019
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An object is released to fall vertically from height of 100m. At the same time another object is projected vertically upward with velocity of 40m/s.
(i) Calculate the time taken before the objects meet
(ii) At what height do the objects meet?
Date posted:
June 1, 2019
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A balloon filled with argon gas of volume 200 cm3 at the earth’s surface where the temperature is 200C, and the pressure 760mm of mercury. If it is allowed to ascend to a height where the temperature is 0C and the pressure 100mm of mercury, calculate the volume of the balloon.
Date posted:
June 1, 2019
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In a faulty mercury-in-glass thermometer was found that the mercury level stands at 3 cm mark in the tube at 00 C and 18 cm when in steam above boiling water at normal atmospheric pressure. Calculate the temperature when the mercury stands at 12 cm mark.
Date posted:
June 1, 2019
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A vernier caliper which had an error of 0.02cm was used to measure the diameter of a spherical marble. If the actual diameter was 3.67cm, draw a vernier caliper scale showing its reading
Date posted:
June 1, 2019
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The speed of green light in a prism is 1.94 x 108m/s.
(i) Determine the refractive index of the prism material. (Speed of light in air = 3.0 x 108m/s).
(ii) Determine the critical angle of the prism material.
Date posted:
June 1, 2019
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A coin is placed beneath a transparent block of thickness 10cm and refractive index 1.56. Calculate the vertical displacement of the coin.
Date posted:
June 1, 2019
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A Bunsen burner flame brought near to the cap of a charged electroscope causes the divergence of the leaf to decrease. Explain these observations.
Date posted:
May 31, 2019
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Explain why sound cannot be heard from far when one shouts in a forest.
Date posted:
May 31, 2019
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A pulley system having a velocity ratio of 4 is used to raise a load of 80N through a height of 0.6m at a constant speed using an effort of 20N in a time of 15 seconds. Calculate the power developed by the effort
Date posted:
May 31, 2019
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A bullet of mass 20g travelling at 400m/s is strapped by a concrete wall. calculate the amount of energy transferred to the wall
Date posted:
May 31, 2019
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A body weighs 40N in air, 30N in water and 35N when in liquid X. Find the relative density of liquid X
Date posted:
May 31, 2019
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Two liquids of density 1100kg/m3 and 850kg/m3 are mixed in equal volumes. The mixture fills a tank of 300cmx 40cm x 50cm to the bring calculate the mass of each liquid
Date posted:
May 31, 2019
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A crane just lifts 9940N when an effort of 116N is applied. Find its velocity ratio if the crane has an efficiency of 72%
Date posted:
May 31, 2019
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A Power station has an input of 30kw at a potential difference of 5kv.A transformer with a secondary coil of 1000 turns is used to step down the voltage to 1000v for transmission along a grid .Assuming there are no power loses in the transformer .calculate.
i) current in the primary coil
ii) The number of turns in the primary coil
iii) The current in the secondary coil
iv) State which of the coils is thick and why
Date posted:
May 31, 2019