From a practical standpoint there are no machines that use energy with 100% efficiency because all movement generates some friction and hence heat and loss of efficiency. Even electrons moving through superconductors generate minute amounts of heat.
From a theoretical standpoint it's impossible to get 100% efficiency; all energy transformations increase entropy. Even if you could devise a machine with no friction, the process of converting energy from one form to another ALWAYS increases entropy. It's a result of the second law of thermodynamics.
No machine can perform with 100% thermodynamic efficiency. The process used by any machine, be it steam, electric, horse drawn, wind, or whatever, can be reduced to a simple description of heat moving from a higher temperature to a lower temperature. The Carnot cycle provides a means to calculate the maximum theoretical efficiency possible. In reality, this maximum efficiency is NEVER achieved due to heat losses, friction, etc. Note that according to the Carnot cycle, 100% efficiency is impossible. The energy input to the machine can NEVER be entirely converted to useful work. Some of the energy is ALWAYS lost as heat to the surroundings.
It really depends on the machine. But in general, friction losses can convert useful energy to heat; the fact that a machine works at a finite speed (i.e., not infinitely slow) causes certain losses (processes that should ideally be isothermal are not - read about the Carnot cycle for more details); there can be other losses such as heat losses, eddy currents, vibrations, etc.
Machines always give off thermal energy. therefore they can't be 100% efficient
Due to losses described by the laws of thermodynamics
All energy transformations increase entropy
Some energy is usually wasted, for example, through friction, eddy currents, hysteresis in magnets, etc. This waste can be reduced, but not completely eliminated.
Friction.
It is always less than 100% Theoretical machines can have efficiencies of 100% but in practice there is always some energy loss Efficiencies of more than 100% are not allowed by the laws of thermodynamics!
The machine efficiency is 35 percent (35/100).
friction and other environmental forces ar responsible for <100 % efficiencies of machines.
No, there is not such thing as an ideal machine; it's just an idea.
No, due to the fact machines loose energy due to heat/thermal energy. you will always loose some amount of energy.
Friction.
A ideal machine would have an efficiency of 100 percent. For this to be possible, the amount of energy output by the machine would equal the amount of energy input. Because all machines have physical parts, some energy is lost to friction, heat dissipation, or other factors, so no machine can be an ideal machine.
frictionIn real machines, as opposed to ideal machines, there is always friction that reduces the efficiency of the machine. Lubricants like oil can be used to reduce friction and improve efficiency.
Some energy is lost to friction.
No physical machine is ideal. Friction is always a loss of energy.
It is always less than 100% Theoretical machines can have efficiencies of 100% but in practice there is always some energy loss Efficiencies of more than 100% are not allowed by the laws of thermodynamics!
The machine efficiency is 35 percent (35/100).
friction and other environmental forces ar responsible for <100 % efficiencies of machines.
No, there is not such thing as an ideal machine; it's just an idea.
nothing has 100% efficiency.
Friction is the force that prevents all machines from being 100 percent efficient. It produces a resisting force that hinders the machine's complete functioning. Reducing friction will enhance efficiency.