Momentum is conserved
60 x m – 40 x m = 2m(v)
60m – 40m = 2m(v)
v = 10m/s2
Kavungya answered the question on May 31, 2019 at 05:55
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The graph below shows the variation of force with distance for a body being towed.
Calculate the total work done on the body.
(Solved)
The graph below shows the variation of force with distance for a body being towed.
Calculate the total work done on the body.
Date posted:
May 31, 2019
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Answers (1)
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Two gear wheel have a 80 teeth (driven) and 20 teeth (driving) and lock with each other. They are fastened on axles of
equal diameters such...
(Solved)
Two gear wheel have a 80 teeth (driven) and 20 teeth (driving) and lock with each other. They are fastened on axles of
equal diameters such that a weight of 150N attached to a string round one axle will just raise 450N on the other axle.
Calculate
(i) M.A
(ii) V.R
(iii) Efficiency of the machine.
Date posted:
May 31, 2019
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Answers (1)
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The figure below shows a car braking system. The brake fluid is an oily liquid.
The brake drum rotates with the wheel of the car.
(i) Explain...
(Solved)
The figure below shows a car braking system. The brake fluid is an oily liquid.
The brake drum rotates with the wheel of the car.
(i) Explain how pushing the brake pedal makes the brake rub against the drum.
(ii) The cross-sectional area of the master piston is 2.0cm2. A force of 140N is applied to the master piston.
(I) Calculate the pressure created in the brake fluid by the master piston.
(II) The cross-sectional area of each slave piston is 2.8cm2. Calculate the force exerted on each slave piston by the brake fluid.
(III) The force exerted on the master piston is greater than the force applied by the foot on the brake pedal. Using the principle of moments, explain this
Date posted:
May 31, 2019
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Answers (1)
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The figure below shows a bottle opener.
A force of 30N is applied at a distance of 11cm from the pivot P. The force F on...
(Solved)
The figure below shows a bottle opener.
A force of 30N is applied at a distance of 11cm from the pivot P. The force F on the bottle cap of 1.5cm from the pivot P. Calculate the force F on the edge of the cap.
Date posted:
May 31, 2019
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Answers (1)
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A heater is rated 3kW, 240V. The fuses available are marked 10A, 13A and 20A. Which fuse is most suitable?
(Solved)
A heater is rated 3kW, 240V. The fuses available are marked 10A, 13A and 20A. Which fuse is most suitable?
Date posted:
May 30, 2019
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Answers (1)
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How many electric iron boxes rated 1000W could be safely connected to a 240V mains circuit fitted with a 13A fuse?
(Solved)
How many electric iron boxes rated 1000W could be safely connected to a 240V mains circuit fitted with a 13A fuse?
Date posted:
May 30, 2019
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Answers (1)
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A ferromagnetic material is being magnetised by single stroking method. On the axes provided, sketch a graph to show how
the strength of the magnet being...
(Solved)
A ferromagnetic material is being magnetised by single stroking method. On the axes provided, sketch a graph to show how
the strength of the magnet being created varies with number of strokes.
Date posted:
May 30, 2019
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Answers (1)
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A metal cube weighs 1.0N in air and 0.8N when totally immersed in water.
Calculate
(i) Volume of water it displaces.
(ii) the density of the cube
(Solved)
A metal cube weighs 1.0N in air and 0.8N when totally immersed in water.
Calculate
(i) Volume of water it displaces.
(ii) the density of the cube
Date posted:
May 30, 2019
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Answers (1)
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A boy on a bicycle accelerated uniformly at 1m/s2 for 10 seconds from an initial velocity of 4m/s. Calculate the distance travelled in this time.
(Solved)
A boy on a bicycle accelerated uniformly at 1m/s2 for 10 seconds from an initial velocity of 4m/s. Calculate the distance travelled in this time.
Date posted:
May 30, 2019
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Answers (1)
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The figure below shows a funnel dipped into a liquid soap solution.
Explain what happens to the soap bubble when the soap is removed.
(Solved)
The figure below shows a funnel dipped into a liquid soap solution.
Explain what happens to the soap bubble when the soap is removed.
Date posted:
May 30, 2019
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Answers (1)
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A solid displaces 8.5cm³ of liquid when floating on a certain liquid and 11.5cm³ when fully submerged with liquid. The
density of solid in 0.8g/cm³, determine:-
i)...
(Solved)
A solid displaces 8.5cm³ of liquid when floating on a certain liquid and 11.5cm³ when fully submerged with liquid. The
density of solid in 0.8g/cm³, determine:-
i) Upthrust on the solid when floating.
ii) Density of the liquid.
Date posted:
May 30, 2019
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Answers (1)
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The figure below shows an empty beaker placed on the top of a pan calibrated in grammes. 50ml of alcohol of density 0.8g/cm3 was added...
(Solved)
The figure below shows an empty beaker placed on the top of a pan calibrated in grammes. 50ml of alcohol of density 0.8g/cm3 was added to the beaker.
Show on the figure the new pointer position.
Date posted:
May 30, 2019
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Answers (1)
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A motor car is uniformly retarded and brought to rest from a speed of 108 km/h in 15 sec. Find its acceleration.
(Solved)
A motor car is uniformly retarded and brought to rest from a speed of 108 km/h in 15 sec. Find its acceleration.
Date posted:
May 30, 2019
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Answers (1)
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A man has 2m³ of concrete delivered to his home and he needed to carry it down in a wheelbarrow. If each barrow load weighs...
(Solved)
A man has 2m³ of concrete delivered to his home and he needed to carry it down in a wheelbarrow. If each barrow load weighs 2500N, how many trips will he have to make?
(Density of concrete = 3000kgm-3).
Date posted:
May 30, 2019
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Answers (1)
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The figure below shows a ray of white light dispersed in a triangular prism. The speed of violet light in the prism in 1.88 ×...
(Solved)
The figure below shows a ray of white light dispersed in a triangular prism. The speed of violet light in the prism in 1.88 × 108m/s.
a) Explain how glass disperses white light into red and violet bands.
b) Determine the refractive index of the prism material for light (take speed of light in vacuum = 3×108m/s
c) Show on the figure the critical angle C for violet light and determine its value.
d) Given that r =21.5° determine the angle
e) On the same figure, sketch the part of red light after white light strikes the prism if the prism was replaced by another of
similar shape but lower refractive index. (Use a dotted line for the answer)
Date posted:
May 30, 2019
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Answers (1)
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Figure below shows a simple barometer.
a) What is the region A?
b) What keeps the mercury in the tube?
c) What is the value of the...
(Solved)
Figure below shows a simple barometer.
a) What is the region A?
b) What keeps the mercury in the tube?
c) What is the value of the atmospheric pressure being shown by the barometer?
d) What would happen to the reading if the barometer were taken up a high mountain.
e) Give a reason for (d) above.
Date posted:
May 30, 2019
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Answers (1)
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The diagram below shows a section of a micrometer screw gauge.
The thimble of the micrometer screw gauge is rotated through two and half revolutions in...
(Solved)
The diagram below shows a section of a micrometer screw gauge.
The thimble of the micrometer screw gauge is rotated through two and half revolutions in the clockwise direction in order to measure the diameter of a marble. State the diameter of the marble if the instrument had a negative error of
0.03mm.
Date posted:
May 30, 2019
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Answers (1)
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The primary coil of a transformer has 1200 turns and the secondary coil has 60 turns. The transformer is connected to a 240 V a.c source. (i) The output...
(Solved)
The primary coil of a transformer has 1200 turns and the secondary coil has 60 turns. The transformer is connected to a 240V a.c source.
i) The output voltage.
ii) The output current when the primary coil has a current of 0.5A (Assume there is no energy losses)
iii) One of the primary ways in which power is lost in transformers is through eddy currents. State how eddy currents can be
minimized.
Date posted:
May 30, 2019
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Answers (1)
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In an experiment to determine the speed of sound, an observer stood in front of a high wall at a distance of 80m. He
clapped two...
(Solved)
In an experiment to determine the speed of sound, an observer stood in front of a high wall at a distance of 80m. He
clapped two boards together at such a rate that each clap coincided with the echo from the wall. A second observer noted
a time of 9.5 seconds starting with first clap and ending with the 21st clap.
i) Calculate the speed of sound under these conditions.
ii) Describe one probable source of error in this experiment.
iii) State one way in which sound wave differ from light waves.
Date posted:
May 30, 2019
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Answers (1)
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A person standing behind a wall hears a bell ringing although he cannot see the bell. What property of sound enables him
to hear the sound?
(Solved)
A person standing behind a wall hears a bell ringing although he cannot see the bell. What property of sound enables him
to hear the sound?
Date posted:
May 30, 2019
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Answers (1)