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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)
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A faulty thermometer records 11oC instead of 0oC and 98oC instead of 100oC. Determine the reading on the thermometer when dipped in liquid at a temperature...
(Solved)
A faulty thermometer records 11oC instead of 0oC and 98oC instead of 100oC. Determine the reading on the thermometer when dipped in liquid at a temperature of 56oC
Date posted:
April 4, 2019
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Answers (1)
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The volume of a bubble at the base of a container of water is 3cm3. The depth of water is
30cm. The bubble rises up the...
(Solved)
The volume of a bubble at the base of a container of water is 3cm3. The depth of water is
30cm. The bubble rises up the column until the surface ;
(i) Explain what happens to the bubble as it rises up the water column
(ii) Determine the volume of the bubble at a point 5cm below the water surface
Date posted:
April 4, 2019
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Answers (1)
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If the trolley was allowed to move down the inclined plane for 4 seconds, calculate the distance
it covers
(Solved)
If the trolley was allowed to move down the inclined plane for 4 seconds, calculate the distance
it covers
Date posted:
April 4, 2019
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Answers (1)
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The velocity-time graph in the figure below illustrates the motion of a ball which has been projected vertically upwards from the surface of the moon....
(Solved)
The velocity-time graph in the figure below illustrates the motion of a ball which has been projected vertically upwards from the surface of the moon. The weight of the object on earth’s surface is 20N, when the acceleration due to gravity is 10ms-2.
(i) State why the velocity becomes negative after 3seconds.
(ii) Determine the acceleration of free fall on the moon showing clearly your work
(iii) Determine the total distance travelled by the ball in 5.0sec
(iv) Find the weight of the ball on the moon
Date posted:
April 4, 2019
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Answers (1)
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Figure below shows a car with a dummy driver before and after a collision test:
(Solved)
Figure below shows a car with a dummy driver before and after a collision test:
The mass of the dummy driver is 90kg. The impact time to reduce the dummy’s speed from
45m/s to zero is 1.2 seconds:
(i) Calculate the average force on the dummy during impact
(ii) State the main energy transformation during the collision
(iii) Calculate how much of the dummy’s energy is transformed during the collision
Date posted:
April 4, 2019
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Answers (1)
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The figure below shows a uniform bar of length 1.0m pivoted near one end. The bar is kept in equilibrium by a spring balance as...
(Solved)
The figure below shows a uniform bar of length 1.0m pivoted near one end. The bar is kept in equilibrium by a spring balance as shown:
Given that the reading of the spring balance is 0.6N, determine the reaction force at the pivot.
Date posted:
April 4, 2019
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Answers (1)
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The diagram below shows a ball being whirled in a vertical plane.
(Solved)
The diagram below shows a ball being whirled in a vertical plane.
Date posted:
April 4, 2019
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Answers (1)