(i) - When the switch is closed current flows through the coil causing a magnetic field.
This repels the magnet towards the chime bar.
- The end of the coil adjacent to the sound pole of the bar magnet acquires a south pole.
ii) – Increase he number of turns in the coil.
- Increase d.c source.
- - Introduce a soft iron core in the coil.
sharon kalunda answered the question on April 4, 2019 at 08:45
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The current capacity of an accumulator is 40Ah. Find the amount of current flowing if the
accumulator is used for 600 minutes
(Solved)
The current capacity of an accumulator is 40Ah. Find the amount of current flowing if the
accumulator is used for 600 minutes
Date posted:
April 4, 2019
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Answers (1)
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In the diagram below, the U-tube contains two liquids; X and Y which do not mix. If the density
of liquid Y is 900Kgm-3 and that...
(Solved)
In the diagram below, the U-tube contains two liquids; X and Y which do not mix. If the density
of liquid Y is 900Kgm-3 and that of X is 1200Kgm-3, calculate the height of liquid Y
Date posted:
April 4, 2019
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Answers (1)
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The figure below shows two mini buses A and B at a speed of 40m/s and 20m/s
respectively moving in opposite directions. They collided head on
(Solved)
The figure below shows two mini buses A and B at a speed of 40m/s and 20m/s
respectively moving in opposite directions. They collided head on
Determine the common speed of the vehicles if they stuck to each other
Date posted:
April 4, 2019
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Answers (1)
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A footballer kicks a ball of 600g initially at rest using a force of 900N. If the foot was in
contact with the ball for 0.1sec....
(Solved)
A footballer kicks a ball of 600g initially at rest using a force of 900N. If the foot was in
contact with the ball for 0.1sec. What was the take off speed of the ball?
Date posted:
April 4, 2019
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Answers (1)
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State the law of inertia
(Solved)
State the law of inertia
Date posted:
April 4, 2019
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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...
(Solved)
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
velocity for 20 seconds. Calculate:
(i) The common velocity
(ii) The distance moved after impact
(iii) The impulse force
(iv) The change in kinetic energy
Date posted:
April 4, 2019
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Answers (1)
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(i) complete the diagram below to show how the pulley can be used to raise a load L by
applying an effort E
(Solved)
(i) complete the diagram below to show how the pulley can be used to raise a load L by
applying an effort E
(ii) The pulley system above has a mechanical advantage of 3. Calculate the total work done
when a load of 60N is raised through a height of 9M
Date posted:
April 4, 2019
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Answers (1)
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A hydraulic machine is used to raise a load of 100kg at a constant velocity through a height
of 2.5m. The radius of the effort piston...
(Solved)
A hydraulic machine is used to raise a load of 100kg at a constant velocity through a height
of 2.5m. The radius of the effort piston is 1.4cm while that of the load piston is 7.0cm. Given
that the machine is 80% efficient, calculate:-
(i) The effort needed
(ii) The energy wasted in using the machine
Date posted:
April 4, 2019
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Answers (1)
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Name one machine that has a velocity ratio of less than one (V.R < 1)
(Solved)
Name one machine that has a velocity ratio of less than one (V.R < 1)
Date posted:
April 4, 2019
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Answers (1)
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The figure below shows a pulley system being used to raise a load.
(Solved)
The figure below shows a pulley system being used to raise a load.
If a load of 100N is raised by applying an effort of 48N, determine the efficiency of
the system.
Date posted:
April 4, 2019
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Answers (1)
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Vicky performed an experiment using a pulley system as shown in the figure.
(Solved)
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
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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
plane is inclined...
(Solved)
An inclined plane of length 5m is used to raise a body of mass 60kg to the back of a lorry. If the
plane is inclined at an angle 25° from the horizontal, calculate the efficiency of the system given
that a constant force of 650 N is used to push the body up the plane
Date posted:
April 4, 2019
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Answers (1)
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Sketch a velocity-time graph for a body moving with zero acceleration
(Solved)
Sketch a velocity-time graph for a body moving with zero acceleration
Date posted:
April 4, 2019
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Answers (1)
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State the three equations of linear motion.
(Solved)
State the three equations of linear motion.
Date posted:
April 4, 2019
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Answers (1)
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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...
(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
deceleration of 4m/s2. Determine the distance traveled by the car from the time the driver
observed the road block until the car comes to rest.
Date posted:
April 4, 2019
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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...
(Solved)
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
(b) Calculate the impulsive force experienced by trolley P
Date posted:
April 4, 2019
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Answers (1)
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A ball of mass 100g is kicked horizontally from the top of a cliff. If the ball takes 4 seconds
to hit the ground, determine the...
(Solved)
A ball of mass 100g is kicked horizontally from the top of a cliff. If the ball takes 4 seconds
to hit the ground, determine the height of the cliff
Date posted:
April 4, 2019
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Answers (1)
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The graph figure below shows displacement –time graph of a in motion
(Solved)
The graph figure below shows displacement –time graph of a in motion
(i) Determine the instanteous velocities at t = 1second and at t = 4 seconds
(ii) Use the results in (i) above to determine the acceleration of the body
Date posted:
April 4, 2019
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Answers (1)
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A parcel is to be dropped from an aeroplane traveling horizontally at 120m/s, at an altitude
of 720m, to fall into a certain village.
Determine
(Solved)
A parcel is to be dropped from an aeroplane traveling horizontally at 120m/s, at an altitude
of 720m, to fall into a certain village.
Determine:
i) The time taken for the parcel to reach the ground
ii) How far ahead of the plane, the village should be when the parcel is released
Date posted:
April 4, 2019
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Answers (1)
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Figure below is a velocity- time graph describing the motion of a particle
(Solved)
Figure below is a velocity- time graph describing the motion of a particle
What does the shaded area represent?
Date posted:
April 4, 2019
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Answers (1)