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In any practical machine, the power output is less than the power input. In other words, the efficiency of real machines is less than 1.
smaller than
always <100%
Wiki User
∙ 13y ago
Wiki User
∙ 11y agoThe power output is always inefficient and usually less than the input because energy is lost by heat and movement etc
Wiki User
∙ 13y agoNo. Some power is used up actually to make the machine work. The ratio of powers output/input is call the efficiency.
Wiki User
∙ 14y agoA. smaller than
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What is the primary type of input and output that is used in the power grid system?
energy
The ratio of output power to input power in percent is called a conductivity b efficiency c work d horsepower?
B.) efficiency
How do machines multiply force without multiplying work?
Work is the (force)*(distance)*(cosine of angle between force and distance). Therefore if you increase the force but the work remains the same either the distance has been reduced or the angle has changed.
What does the efficiency of a machine describe?
The efficiency of a machine is: (useful energy that comes out of the machine) divided by (energy put into the machine). It's really handy to know this before you spend a million dollars on a machine, and discover that even though you put enough energy into it to do the job, you're not getting enough out, and the job isn't getting done. Example: You need 100 watts of light dispersed in a room. You buy a 100-watt light bulb, screw it in, turn it on, and nobody in the room can read anything. You lose, because you failed to consider that the efficiency of the type of light bulb you bought is about 35%. That means for every 100 watts of electricity you put into the bulb, you get about 35 watts of light out of it. The other 65 watts of power comes out of the bulb in the form of heat. (Which explains why the air conditioning runs more when the lights are on.) Had you considered the 35% efficiency of the light bulb, and knowing that you needed 100 watts of light, you would have known to buy a bulb rated at (100 / 0.35) = 286 watts.
Unit of power used mainly in the US?
This depends on the situation. The main power unit used for electric power output is generally the Watt (W), while the main power unit used for mechanical power output is often the horsepower (hp).
What is a a comparison of a machines work output with the works input that is mechanical?
Output power divided by input power, for a machine, is called the machine's efficiency. It need not be mechanical energy.
How is the efficiency of a machine calculated?
Efficiency = useful output power / input power
In a paractical machine the power output is the power input?
smaller thanalways
How is a machine's efficiency of a calculated?
Efficiency = useful output power / input power
What is the efficiency of the machine?
a machine applies a force of 100 newtons over a distance of 10 meters to raise a500 newtons drum 1.5 meters. what is efficiency of the machine ?
What is efficiency and how is it calculated?
The efficiency is output divided by input.
Is your power into motor equal to your power out of motor at no load?
For a motor's output power to equal its input power, the motor's efficiency must be 100%. As no machine, particularly a rotating machine, can possibly achieve 100% efficiency, there is no condition under which its output power can ever match its input power.
In a practical machine the power output is equal to the power input?
No, because of inefficiencies which usually cause heat, or heat in unwanted places. Or wear of parts. The total power in always appears somwhere in some form, not always where it is wanted.
How the efficiency of machine be obtained?
Efficiency is output power divided by input power. You somehow have to measure, calculate, or estimate both; the details will vary depending on the type of energy input and energy output.
How is the efficiency of a compound machine calculated?
The efficiency of a machine is found by dividing the amount of work done by a machine by the amount of energy used by a machine. The answer is then multiplied by 100 to give a percentage.
Why in a real machine the output work is always less the input work?
In a real machine, part of the energy (or power) is always wasted.
Does a machine with an efficiency of 1.2 requires a smaller effort force than a machine that has an efficiency of 2.2?
Efficiency is a measure of power losses. A machine with an efficiency of say 85% or 0.85, experiences 15% power losses from input to output (as heat through friction) This would be typical for say a car, comparing crankshaft power to power at the drive wheels. No machine will exceed 100% efficiency > Work done = force * distance Efficiency = work done at output / work done at input > Mechanical Advantage (leverage) is distance moved by input / distance moved by output. Output force = input force * Mechanical Advantage
