Advantages of friction
? Makes walking, writing possible.
? Required for braking in cars, bicycles etc.
? Makes rotation of the conveyor belts in factories possible.
? Necessary for lighting matchsticks.
? Useful when using nuts, bolts, screw jacks, vices etc.
Moraa orina answered the question on April 9, 2018 at 09:27
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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
suspended from a light inextensible string so that it can swing freely. Find:
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
the change in momentum produced by the force and the time it takes the car to come to rest.
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)
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A particle moving with a velocity of 200m/s is brought to rest in 0.02s. What is the acceleration of the particle?
(Solved)
A particle moving with a velocity of 200m/s is brought to rest in 0.02s. What is the acceleration of the
particle?
Date posted:
April 8, 2018
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Answers (1)
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A body moves 30m due east in 2seconds, then 40m due north in 4seconds. Determine its:a) Average speed.
(Solved)
A body moves 30m due east in 2seconds, then 40m due north in 4seconds. Determine its:
a) Average speed.
Date posted:
April 8, 2018
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Answers (1)
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Explain why in water the meniscus in the capillary tube is higher than in the beaker while in the mercury, the meniscus in the capillary tube is lower than in the beaker
(Solved)
Explain why in water the meniscus in the capillary tube is higher than in the beaker while in the mercury, the meniscus in the capillary tube is lower than in the beaker.
Date posted:
April 8, 2018
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Answers (1)
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A body covers a distance of 2m in 4seconds, rests for 2seconds and finally covers a distance of 90m in 6seconds. Calculate its average speed.
(Solved)
A body covers a distance of 2 m in 4 seconds, rests for 2 seconds and finally covers a distance of 90 m in
6seconds. Calculate its average speed.
Date posted:
April 8, 2018
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Answers (1)
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State the dangers of Bernoulli’s effect
(Solved)
State the dangers of Bernoulli’s effect
Date posted:
April 8, 2018
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Answers (1)
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Explain the applications of Bernoulli’s principle
(Solved)
Explain the applications of Bernoulli’s principle
Date posted:
April 8, 2018
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Answers (1)