| Your Results | Global Average | |
|---|---|---|
| Questions | 5 | 5 |
| Correct | 0 | 3.13 |
| Score | 0% | 63% |
What type of load doesn't create specific stress points or vary with time?
concentrated load |
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non-uniformly distributed load |
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static uniformly distributed load |
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impact 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.
Torque involves a perpendicular force applied to a lever arm that moves around a center of rotation. Increasing the length of the lever arm will do which of the following?
increase applied force |
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increase torque |
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decrease torque |
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decrease applied force |
Torque measures force applied during rotation: τ = rF. Torque (τ, the Greek letter tau) = the radius of the lever arm (r) multiplied by the force (F) applied. Radius is measured from the center of rotation or fulcrum to the point at which the perpendicular force is being applied. The resulting unit for torque is newton-meter (N-m) or foot-pound (ft-lb).
Boyle's law defines the relationship between pressure and volume as:
\(\frac{P_1}{P_2} = \frac{V_1}{V_2}\) |
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\({P_1}{P_2} = {V_1}{V_2}\) |
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\(\frac{P_1}{P_2} = {V_1}{V_2}\) |
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\(\frac{P_1}{P_2} = \frac{V_2}{V_1}\) |
Boyle's law states that "for a fixed amount of an ideal gas kept at a fixed temperature, pressure and volume are inversely proportional". Expressed as a formula, that's \(\frac{P_1}{P_2} = \frac{V_2}{V_1}\)
The force amplification achieved by using a tool, mechanical device or machine system is called:
work |
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power |
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efficiency |
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mechanical advantage |
Mechanical advantage is a measure of the force amplification achieved by using a tool, mechanical device or machine system. Such a device utilizes input force and trades off forces against movement to amplify and/or change its direction.
Power is the rate at which:
work is done |
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potential energy is converted into kinetic energy |
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input force is transferred to output force |
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friction is overcome |
Power is the rate at which work is done, P = w/t, or work per unit time. The watt (W) is the unit for power and is equal to 1 joule (or newton-meter) per second. Horsepower (hp) is another familiar unit of power used primarily for rating internal combustion engines. 1 hp equals 746 watts.