| Your Results | Global Average | |
|---|---|---|
| Questions | 5 | 5 |
| Correct | 0 | 2.85 |
| Score | 0% | 57% |
Force of friction due to kinetic friction is __________ the force of friction due to static friction.
the same as |
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opposite |
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higher than |
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lower than |
The formula for force of friction (Ff) is the same whether kinetic or static friction applies: Ff = μFN. To distinguish between kinetic and static friction, μk and μs are often used in place of μ.
Which of the following represents the force a surface exerts when an object presses against it?
counter force |
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normal force |
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friction |
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mass |
Normal force (FN) represents the force a surface exerts when an object presses against it.
A box is resting on a smooth floor. Static friction is present:
only if normal force is present |
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when an attempt is made to move the box |
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if the coefficient of friction is greater than one |
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at all times |
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 is not a type of bridge?
cable |
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truss |
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arch |
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block |
The six basic bridge forms are beam, truss, arch, cantilever, cable, and suspension.
According to Boyle's law, for a fixed amount of gas kept at a fixed temperature, which of the following are inversely proportional?
volume, mass |
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pressure, volume |
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density, volume |
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pressure, density |
Boyle's law states that "for a fixed amount of an ideal gas kept at a fixed temperature, pressure and volume are inversely proportional".