| Your Results | Global Average | |
|---|---|---|
| Questions | 5 | 5 |
| Correct | 0 | 3.38 |
| Score | 0% | 68% |
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 |
|
pressure, volume |
|
density, volume |
|
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".
Which of the following is not a characteristic of a ceramic?
high melting point |
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low density |
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chemically stable |
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low corrosive action |
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.
| 21.36 lbs. | |
| 8 lbs. | |
| 29.96 lbs. | |
| 11 lbs. |
The mechanical advantage of a wheel and axle is the input radius divided by the output radius:
MA = \( \frac{r_i}{r_o} \)
In this case, the input radius (where the effort force is being applied) is 8 and the output radius (where the resistance is being applied) is 3 for a mechanical advantage of \( \frac{8}{3} \) = 2.67
MA = \( \frac{load}{effort} \) so effort = \( \frac{load}{MA} \) = \( \frac{80 lbs.}{2.67} \) = 29.96 lbs.
What type of load acts on a relatively small area of a structure?
dynamic load |
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impact load |
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concentrated load |
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non-uniformly distributed load |
A concentrated load acts on a relatively small area of a structure, a static uniformly distributed load doesn't create specific stress points or vary with time, a dynamic load varies with time or affects a structure that experiences a high degree of movement, an impact load is sudden and for a relatively short duration and a non-uniformly distributed load creates different stresses at different locations on a structure.
An object's resistance to changes in direction is known as:
kinetic energy |
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mass |
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inertia |
|
weight |
The more mass a substance has the more force is required to move it or to change its direction. This resistance to changes in direction is known as inertia.