First, because there is NO way to reduce the minimum amount of energy required to complete a task. You can't get something for nothing. But also because often it is easier to apply force (aka do work) in one direction and not another, like when using a pulley. You direct force down to lift a load up. It is also sometimes easier to apply a little force for a longer distance than apply and large force very quickly, like while pushing something up an inclined plane, wedge, or screw. Other times, it is necessary to exchange force for speed. Baseball players are very strong, but their arms cannot physically move as fast as they need to go to propel the ball, so they apply a lot of force in moving the bat, which moves very fast. The opposite is also true. In a screw driver, speed is not important but force is. Your hand moves the screw driver relatively quickly while the screw driver applies a larger force at a much slower rate.
If the machine doesn't decrease the amount of work that you do, it might still improve the quality of the final result of your efforts.
Yes, usually it will decrease it, since no machine is 100% efficient.Just in case you mean "the amount of work REQUIRED", then of course the machine will INCREASE that.
a machine does NOT decrease the amount of work one does, rather, it changes the way one does work in some way. for example, if one were to use a lever to lift a weight, the object would have to go farther to get to the desired height, but it would require less energy to move, so all in all, it would even itself out, (unless you include friction and other laws of physics, then, it would require more work).
dont buy or use so much
it is the amount of work that can be done. a machine can use 300,000 J of energy but it only uses 263,000 J. that is percent efficiency.
The most common exercise machine to run on would be the treadmill. You can use this machine at various speeds and inclines to increase or decrease your workout. They also have timed programs you can choose as well.
If the amount of itemized deductions is more than your standard deduction the amount over your standard deduction amount would decrease your taxable income amount and this would decrease your federal income tax liability.
You can reduce the amount of papers used, decrease the amount of bags and use your own cloth bags, and you can reduce the amount of paper plates and cups and use your own.
Machine B will use more power.