| Your Results | Global Average | |
|---|---|---|
| Questions | 5 | 5 |
| Correct | 0 | 3.09 |
| Score | 0% | 62% |
Which of the following is not a type of bridge?
truss |
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block |
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arch |
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cable |
The six basic bridge forms are beam, truss, arch, cantilever, cable, and suspension.
Depending on where you apply effort and resistance, the wheel and axle can multiply:
power or distance |
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speed or power |
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force or speed |
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force or distance |
If you apply the resistance to the axle and the effort to the wheel, the wheel and axle will multiply force and if you apply the resistance to the wheel and the effort to the axle, it will multiply speed.
The force required to initally get an object moving is __________ the force required to keep it moving.
higher than |
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the same as |
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lower than |
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opposite |
For any given surface, the coefficient of static friction is higher than the coefficient of kinetic friction. More force is required to initally get an object moving than is required to keep it moving. Additionally, static friction only arises in response to an attempt to move an object (overcome the normal force between it and the surface).
Which of the following will increase the mechanical advantage of a second-class lever?
move the fulcrum between the force and the object being lifted |
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move the object being lifted closer to the fulcrum |
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decrease the length of the lever |
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move the object being lifted farther away from the fulcrum |
A second-class lever is used to increase force on an object in the same direction as the force is applied. This lever requires a smaller force to lift a larger load but the force must be applied over a greater distance. The fulcrum is placed at one end of the lever and mechanical advantage increases as the object being lifted is moved closer to the fulcrum or the length of the lever is increased. An example of a second-class lever is a wheelbarrow.
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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the portions of the system at an altitude below the input |
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all of these are correct |
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everywhere in the system |
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.