| Your Results | Global Average | |
|---|---|---|
| Questions | 5 | 5 |
| Correct | 0 | 2.90 |
| Score | 0% | 58% |
The advantage of using a third-class lever is that it increases:
the force applied to the load |
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the mechanical advantage of the lever |
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the speed of the load |
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the distance traveled by the load |
A third-class lever is used to increase distance traveled by an object in the same direction as the force applied. The fulcrum is at one end of the lever, the object at the other, and the force is applied between them. This lever does not impart a mechanical advantage as the effort force must be greater than the load but does impart extra speed to the load. Examples of third-class levers are shovels and tweezers.
Which of the following is not a characteristic of a ceramic?
high melting point |
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low density |
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low corrosive action |
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chemically stable |
Ceramics are mixtures of metallic and nonmetallic elements that withstand exteme thermal, chemical, and pressure environments. They have a high melting point, low corrosive action, and are chemically stable. Examples include rock, sand, clay, glass, brick, and porcelain.
For a hydraulic system, pressure applied to the input of the system will increase the pressure in which parts of the system?
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 |
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the portions of the system at an altitude above the input |
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.
The force required to initally get an object moving is __________ the force required to keep it moving.
lower than |
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opposite |
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higher than |
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the same as |
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).
The science that deals with motion and the forces that produce motion is called which of the following?
engineering |
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mechanics |
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physics |
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aeronautics |
Mechanics deals with motion and the forces that produce motion.