-Transformers step up voltage to higher value for transmission which minimizes
power loss.
- They also step down higher voltage to the voltage required by the consumers.
sharon kalunda answered the question on April 4, 2019 at 08:53
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Date posted: April 4, 2019. Answers (1)
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(i) Draw on the diagram, the shape of the magnetic field inside and outside the coil when the
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If the jockey J on the rheostat is moved towards Q what’s the effect on:-
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Date posted: April 4, 2019. Answers (1)
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Determine the common speed of the vehicles if they stuck to each other
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Date posted: April 4, 2019. Answers (1)
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Date posted: April 4, 2019. Answers (1)
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A minibus of mass 2000kg traveling at a constant velocity of 36km/h collides with a stationary
car of mass 1000kg. The impact takes 2 seconds before the two move together at a constant
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(i) The common velocity
(ii) The distance moved after impact
(iii) The impulse force
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Date posted: April 4, 2019. Answers (1)
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Date posted: April 4, 2019. Answers (1)
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(i) The effort needed
(ii) The energy wasted in using the machine
Date posted: April 4, 2019. Answers (1)
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Date posted: April 4, 2019. Answers (1)
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If a load of 100N is raised by applying an effort of 48N, determine the efficiency of
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Date posted: April 4, 2019. Answers (1)
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Vicky performed an experiment using a pulley system as shown in the figure.
(a) What is the V.R. of the system?
(b) Determine the M.A. of the system. *
(c) Calculate the efficiency of the system.
(d) Explain why efficiency of a practical machine is always less than 100%
(e) If the load moves a distance of 5 cm. Find the work done on the load.
Date posted: April 4, 2019. Answers (1)
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An inclined plane of length 5m is used to raise a body of mass 60kg to the back of a lorry. If the
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Date posted: April 4, 2019. Answers (1)
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He takes 0.5 s before applying the brakes which brings the...(Solved)
A car is traveling uniformly at 100km/hr when the driver observes a road block ahead.
He takes 0.5 s before applying the brakes which brings the car to rest with a uniform
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Date posted: April 4, 2019. Answers (1)
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In an experiment on momentum, trolley P of mass 800g was attached to a ticker timer of
frequency 50Hz. Trolley P, initially moving with a velocity of 0.5m/s, was made to collide
with a stationary trolley Q of mass 400g. A copy of the tape as it appeared after the collision is
presented in the figure below:-
a) Determine the velocity of the trolley P after collision
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Date posted: April 4, 2019. Answers (1)
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Date posted: April 4, 2019. Answers (1)