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GG16
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Hi
an help would be appreciated
an electric motor of input power 100w raises a mass of 10kg vertically at a steady speed of 0.5ms. What is the efficiency of the system
an help would be appreciated
an electric motor of input power 100w raises a mass of 10kg vertically at a steady speed of 0.5ms. What is the efficiency of the system
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DanielDaniels
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#2
(Original post by GG16)
Hi
an help would be appreciated
an electric motor of input power 100w raises a mass of 10kg vertically at a steady speed of 0.5ms. What is the efficiency of the system
Hi
an help would be appreciated
an electric motor of input power 100w raises a mass of 10kg vertically at a steady speed of 0.5ms. What is the efficiency of the system
Can you work out the answer from here?
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Smithenator5000
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#3
(Original post by GG16)
Hi
an help would be appreciated
an electric motor of input power 100w raises a mass of 10kg vertically at a steady speed of 0.5ms. What is the efficiency of the system
Hi
an help would be appreciated
an electric motor of input power 100w raises a mass of 10kg vertically at a steady speed of 0.5ms. What is the efficiency of the system
You should be able to calculate the output power as using the applied force (equal to the object's weight in this case) and the speed of ascent. You should use the equation
. You can then find the efficiency by dividing this by the input power and if they want it as a percentage, multiply it by 
.I hope that this has been helpful.
Smithenator5000.
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RogerOxon
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#4
(Original post by GG16)
an electric motor of input power 100w raises a mass of 10kg vertically at a steady speed of 0.5ms. What is the efficiency of the system
an electric motor of input power 100w raises a mass of 10kg vertically at a steady speed of 0.5ms. What is the efficiency of the system
(You should get an answer of somewhere close to 50%)
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Physics Enemy
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#5
(Original post by GG16)
Electric motor of input power 100 W raises mass of 10 kg vertically at steady speed 0.5 ms^-1. What is the efficiency of the system?
Electric motor of input power 100 W raises mass of 10 kg vertically at steady speed 0.5 ms^-1. What is the efficiency of the system?
Took 100 W of electrical input power to attain that.
Efficiency = (Output/Input) x 100% = 49.1%
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Subhawk
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Callicious
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(Original post by Subhawk)
why did you times by 9.81, i dont understand
why did you times by 9.81, i dont understand
Power = Force * Velocity
Get Force (weight) and you know velocity
Hence have the power actually needed to lift the object (the output)
You're given the input
Efficiency is input/output * 100
You need 9.81 to calculate the weight (force)
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