| Your Results | Global Average | |
|---|---|---|
| Questions | 5 | 5 |
| Correct | 0 | 3.01 |
| Score | 0% | 60% |
Which of the following is not a type of simple machine?
gear |
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screw |
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lever |
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pulley |
The six types of simple machines are the lever, wheel and axle, pulley, inclined plane, wedge, and screw.
The measure of how much of the power put into a machine is turned into movement or force is called:
mechanical advantage |
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power |
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force multiplication |
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efficiency |
The efficiency of a machine describes how much of the power put into the machine is turned into movement or force. A 100% efficient machine would turn all of the input power into output movement or force. However, no machine is 100% efficient due to friction, heat, wear and other imperfections that consume input power without delivering any output.
For a hydraulic system, pressure applied to the input of the system will increase the pressure in which parts of the system?
the portions of the system at an altitude above the input |
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everywhere in the system |
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the portions of the system at an altitude below the input |
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all of these are correct |
Pascal's law states that a pressure change occurring anywhere in a confined incompressible fluid is transmitted throughout the fluid such that the same change occurs everywhere. For a hydraulic system, this means that a pressure applied to the input of the system will increase the pressure everywhere in the system.
A fixed pulley has a mechanical advantage of:
2 |
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1 |
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-1 |
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0 |
A fixed pulley is used to change the direction of a force and does not multiply the force applied. As such, it has a mechanical advantage of one. The benefit of a fixed pulley is that it can allow the force to be applied at a more convenient angle, for example, pulling downward or horizontally to lift an object instead of upward.
The work done by the sum of all forces acting on a particle equals the change in the kinetic energy of the particle. This defines which of the following?
work-energy theorem |
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mechanical advantage |
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conservation of mechanical energy |
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Pascal's law |
The work-energy theorem states that the work done by the sum of all forces acting on a particle equals the change in the kinetic energy of the particle. Simply put, work imparts kinetic energy to the matter upon which the work is being done.