1. Constant temperature
2. No mechanical strain
johnmulu answered the question on February 14, 2017 at 13:25
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A current of 0.70 A flows through a wire when a p.d. of 0.35 V is applied at the ends of the wire. If the wire is 0.5 m long...
(Solved)
A current of 0.70 A flows through a wire when a p.d. of 0.35 V is applied at the ends of the wire. If the wire is 0.5 m long and has a cross section area of 8.0 x 10-3m2. Determine its resistivity.
Date posted:
February 14, 2017
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Answers (1)
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A circuit consists of a battery, a metal wire, an ammeter and a switch connected in series. The switch is closed and the ammeter reading noted
(Solved)
A circuit consists of a battery, a metal wire, an ammeter and a switch connected in series. The switch is closed and the ammeter reading noted. The metal wire is now heated. State the observations made on the ammeter reading and give a reason for your answer.
Date posted:
February 14, 2017
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Answers (1)
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State the reason why a voltmeter of high resistance is more accurate in measuring potential differences than one of low resistance.
(Solved)
State the reason why a voltmeter of high resistance is more accurate in measuring potential differences than one of low resistance.
Date posted:
February 14, 2017
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Answers (1)
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In large current circuits, large resistors in parallel are preferred to low resistors in series. Explain
(Solved)
In large current circuits large resistors in parallel are preferred to low resistors in series. Explain.
Date posted:
February 14, 2017
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Answers (1)
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Define the term velocity ratio of a machine
(Solved)
Define the term velocity ratio of a machine.
Date posted:
February 14, 2017
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Answers (1)
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State two reasons why the efficiency of a pulley system is always less than 100%
(Solved)
State two reasons why the efficiency of a pulley system is always less than 100%.
Date posted:
February 14, 2017
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Answers (1)
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A cyclist initially at rest moved down a hill without pedaling. He applied brakes and eventually stopped
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A cyclist initially at rest moved down a hill without pedaling. He applied brakes and eventually stopped. State the energy changes as the cyclist moved down the hill.
Date posted:
February 14, 2017
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Answers (1)
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Define the term efficiency of a machine
(Solved)
Define the term efficiency of a machine.
Date posted:
February 14, 2017
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Answers (1)
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A certain machine uses an effort of 400 N to raise a load of 60 0N. If the efficiency of the machine is 75%, determine its velocity ratio
(Solved)
A certain machine uses an effort of 400 N to raise a load of 600N. If the efficiency of the machine is 75%, determine its velocity ratio.
Date posted:
February 14, 2017
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Answers (1)
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A crane lift a load of 2000 kg through a vertical distance of 3.0 m in 6 seconds. Determine the (i) Work done
(Solved)
A crane lift a load of 2000 kg through a vertical distance of 3.o m in 6 seconds.Determine the:
i) Work done
ii) Power development by the crane
iii) Efficiency of the crane given that it is operated by an electric motor rated 12.5 KW.
Date posted:
February 14, 2017
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Answers (1)
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A certain machine raises 2.0 tonnes of water through 22 metres. If the efficiency of the machine is 80%, how much work is done on the machine?
(Solved)
A certain machine raises 2.0 tonnes of water through 22 metres. If the efficiency of the machine is 80%, how much work is done on the machine?
Date posted:
February 14, 2017
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Answers (1)
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If a load on 100 N is raised by applying an effort of 28 N, determine the efficiency of the system
(Solved)
If a load on 100 N is raised by applying an effort of 28 N, determine the efficiency of the system.
Date posted:
February 14, 2017
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Answers (1)
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A body of mass M is allowed to slide down an inclined plane. State two factors that affects its final velocity at the bottom of the incline.
(Solved)
A body of mass M is allowed to slide down an inclined plane. State two factors that affects its final velocity at the bottom of the incline.
Date posted:
February 14, 2017
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Answers (1)
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State the reason why the amplitude of a simple pendulum decrease with time
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State the reason why the amplitude of a simple pendulum decrease with time.
Date posted:
February 14, 2017
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Answers (1)
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Name a device used to convert light energy directly into electrical energy
(Solved)
Name a device used to convert light energy directly into electrical energy.
Date posted:
February 14, 2017
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Answers (1)
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A horizontal force of 12 N is applied on a wooden block of mass 2 kg placed on a horizontal surface. It causes the block to accelerate at 5 ms-2
(Solved)
A horizontal force of 12N is applied on a wooden block of mass 2 kg placed on a horizontal surface. It causes the block to accelerate at 5 ms-2. Determine the frictional force between the block and the surface.
Date posted:
February 14, 2017
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Answers (1)
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A student pulls a block of wood along a horizontal surface by applying a constant force. State the reason why the block moves at a constant velocity
(Solved)
A student pulls a block of wood along a horizontal surface by applying a constant force. State the reason why the block moves at a constant velocity.
Date posted:
February 14, 2017
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Answers (1)
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A car of mass 30 kg is pushed along a horizontal path by horizontal force of 8 N and moves with a constant velocity.
(Solved)
A car of mass 30 kg is pushed along a horizontal path by horizontal force of 8 N and moves with a constant velocity. The force is then increased to 14N. Determine:
a) The resistance to the motion of the cart;
b) The acceleration of the cart.
Date posted:
February 14, 2017
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Answers (1)
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State Newton's second law of motion
(Solved)
State Newton's second law of motion.
Date posted:
February 14, 2017
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Answers (1)
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A footballer kicks a ball of mass 0.6 kg initially at rest using a force of 720N. If the foot was in contact with the ball for 0.1 seconds, what was the takeoff speed of the ball?
(Solved)
A footballer kicks a ball of mass 0.6 kg initially at rest using a force of 720N. If the foot was in contact with the ball for 0.1 seconds, what was the takeoff speed of the ball?
Date posted:
February 14, 2017
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Answers (1)