W=½(ke2)= ½(25)(0.12).
=0.125J
Moraa orina answered the question on April 9, 2018 at 16:39
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A crane is used to lift a body of mass 30kg through a vertical distance of 5.0m.
a) How much work is done on the...
(Solved)
A crane is used to lift a body of mass 30kg through a vertical distance of 5.0m.
a) How much work is done on the body?
b) What is the potential energy stored in the body?
c) Comment on the two answers above.
Date posted:
April 9, 2018
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Answers (1)
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A force of 40N is applied on a body. The body moves a horizontal distance of 7m. Calculate the work done on the body.
(Solved)
A force of 40N is applied on a body. The body moves a horizontal distance of 7m. Calculate the work done
on the body.
Date posted:
April 9, 2018
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Answers (1)
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(Solved)
State possible ways of reducing friction
Date posted:
April 9, 2018
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Answers (1)
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Explain why a magnetic material is attracted by a magnet
(Solved)
Explain why a magnetic material is attracted by a magnet
Date posted:
April 9, 2018
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Answers (1)
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State the limitations of friction
(Solved)
State the limitations of friction.
Date posted:
April 9, 2018
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Answers (1)
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State the advantages of friction
(Solved)
State the advantages of friction
Date posted:
April 9, 2018
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Answers (1)
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A bullet of mass 2g travelling horizontally at 20m/s embeds itself in a block of wood of mass 990g suspended from a light inextensible...
(Solved)
A bullet of mass 2g travelling horizontally at 20m/s embeds itself in a block of wood of mass 990g
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The velocity of the bullet and block immediately after collision.
Date posted:
April 9, 2018
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Answers (1)
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A 5kg mass moving with a velocity of 2m/s collides with a 2kg mass moving at 7m/s along the same line.
If the two masses...
(Solved)
A 5kg mass moving with a velocity of 2m/s collides with a 2kg mass moving at 7m/s along the same line.
If the two masses join together on impact, find their common velocity if they were moving:
a) In opposite directions.
b) In the same direction.
Date posted:
April 9, 2018
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Answers (1)
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. A bullet of mass 20g is shot from a gun of mass 20kg with a muzzle velocity of 200m/s. if the bullet is
30cm...
(Solved)
A bullet of mass 20g is shot from a gun of mass 20kg with a muzzle velocity of 200m/s. if the bullet is
30cm long, determine:
a) The acceleration of the bullet.
b) The recoil velocity of the gun.
Date posted:
April 9, 2018
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Answers (1)
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Differentiate between elastic collision ana inelastic collision
(Solved)
Differentiate between elastic collision ana inelastic collision
Date posted:
April 9, 2018
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Answers (1)
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A car of mass 1500kg is brought to rest from a velocity of 25m/s by a constant force of 3000N. Determine
the change in momentum...
(Solved)
A car of mass 1500kg is brought to rest from a velocity of 25m/s by a constant force of 3000N. Determine
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Date posted:
April 9, 2018
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Answers (1)
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Explain why the bristles of a paint brush cling together when removed from water in a bucket
(Solved)
Explain why the bristles of a paint brush cling together when removed from water in a bucket.
Date posted:
April 9, 2018
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Answers (1)
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A man of mass 75kg stands on a weighing machine in a lift. Determine the reading on the weighing
machine when the lift:
a) Ascends with...
(Solved)
A man of mass 75kg stands on a weighing machine in a lift. Determine the reading on the weighing
machine when the lift:
a) Ascends with an acceleration of 2m/s5.
b) Descends at a constant velocity of 1.5m/s
c) Descends with an acceleration of 5.5m/s5
Date posted:
April 9, 2018
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Answers (1)
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A man of mass 75kg stands on a weighing machine in a lift. Determine the reading on the weighing machine when the lift:a) Ascends...
(Solved)
A man of mass 75kg stands on a weighing machine in a lift. Determine the reading on the weighing
machine when the lift:
a) Ascends with an acceleration of 2m/s5.
b) Descends at a constant velocity of 1.5m/s5.
c) Descends with an acceleration of 5.5m/s
Date posted:
April 8, 2018
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Answers (1)
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A ball of mass 35g travelling horizontally at 20m/s strikes a barrier normally and rebounds with a speed
of 3m/s. Find the impulse exerted on...
(Solved)
A ball of mass 35g travelling horizontally at 20m/s strikes a barrier normally and rebounds with a speed
of 3m/s. Find the impulse exerted on the ball.
Date posted:
April 8, 2018
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Answers (1)
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Two stones of mass 8kg and 4kg move with velocities 3m/s and 6m/s respectively. Compare their momentum.
(Solved)
Two stones of mass 8kg and 4kg move with velocities 3m/s and 6m/s respectively. Compare their
momentum.
Date posted:
April 8, 2018
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Answers (1)
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Jet fighter on practice moving at a velocity of 20m/s released a bomb above the ground which hits the ground after 3s. Calculate:a) the distance...
(Solved)
Jet fighter on practice moving at a velocity of 20m/s released a bomb above the ground which hits the
ground after 3s. Calculate:
a) the distance from the ground to the jet,
b)the horizontal distance from the target when the bomb is released.
Date posted:
April 8, 2018
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Answers (1)
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A stone is thrown at a velocity of 30m/s to the horizontal by a girl at the top of a tree whose height is 30m....
(Solved)
A stone is thrown at a velocity of 30m/s to the horizontal by a girl at the top of a tree whose height is 30m.
Calculate:
a) the time taken for the stone to strike the ground.
b) the velocity at which the stone strikes the ground.
Date posted:
April 8, 2018
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Answers (1)
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An object is released to fall vertically from a height of 20m. At the same time, another object is projected
vertically upwards with a velocity...
(Solved)
An object is released to fall vertically from a height of 20m. At the same time, another object is projected
vertically upwards with a velocity of 40m/ss
a)Calculate the time taken before the two objects meet
b) At what height above the point of projection do they meet?
Date posted:
April 8, 2018
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Answers (1)
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A particle travelling in a straight line at 2m/s is uniformly accelerated at 5m/s2 for 8seconds. Calculate the displacement of the particle.
(Solved)
A particle travelling in a straight line at 2m/s is uniformly accelerated at 5m/s2 for 8seconds. Calculate the displacement of the particle.
Date posted:
April 8, 2018
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Answers (1)