| Your Results | Global Average | |
|---|---|---|
| Questions | 5 | 5 |
| Correct | 0 | 3.23 |
| Score | 0% | 65% |
Coplanar forces:
pass through a common point |
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have opposite dimensions |
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act along the same line of action |
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act in a common plane |
Collinear forces act along the same line of action, concurrent forces pass through a common point and coplanar forces act in a common plane.
A watt is the unit for which of the following?
work |
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power |
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energy |
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mechanical advantage |
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.
The mass of an object correlates to the size of the object but ultimately depends on:
gravity |
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the object's weight |
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the object's potential energy |
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the object's density |
Mass is a measure of the amount of matter in an object. In general, larger objects have larger mass than smaller objects but mass ultimately depends on how compact (dense) a substance is.
What type of load is sudden and for a relatively short duration?
impact load |
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non-uniformly distributed load |
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concentrated load |
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dynamic 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.
Which of these will have the most impact on the kinetic energy of an object?
its direction |
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its mass |
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its weight |
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its speed |
Kinetic energy is the energy of movement and is a function of the mass of an object and its speed: \(KE = {1 \over 2}mv^2\) where m is mass in kilograms, v is speed in meters per second, and KE is in joules. The most impactful quantity to kinetic energy is velocity as an increase in mass increases KE linearly while an increase in speed increases KE exponentially.