| Your Results | Global Average | |
|---|---|---|
| Questions | 5 | 5 |
| Correct | 0 | 3.09 |
| Score | 0% | 62% |
The mass of an object correlates to the size of the object but ultimately depends on:
the object's density |
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gravity |
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the object's potential energy |
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the object's weight |
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 doesn't create specific stress points or vary with time?
concentrated load |
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impact load |
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non-uniformly distributed load |
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static 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.
| 0.71 ft. | |
| 0 ft. | |
| 0.54 ft. | |
| 2.14 ft. |
To balance this lever the torques on each side of the fulcrum must be equal. Torque is weight x distance from the fulcrum so the equation for equilibrium is:
Rada = Rbdb
where a represents the left side of the fulcrum and b the right, R is resistance (weight) and d is the distance from the fulcrum.Solving for db, our missing value, and plugging in our variables yields:
db = \( \frac{R_ad_a}{R_b} \) = \( \frac{15 lbs. \times 5 ft.}{35 lbs.} \) = \( \frac{75 ft⋅lb}{35 lbs.} \) = 2.14 ft.
What type of load creates different stresses at different locations on a structure?
non-uniformly distributed load |
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static uniformly distributed load |
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impact 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.
Two gears are connected and the smaller gear drives the larger gear. The speed of rotation will __________ and the torque will __________.
decrease, increase |
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decrease, decrease |
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increase, increase |
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increase, decrease |
Connected gears of different numbers of teeth are used together to change the rotational speed and torque of the input force. If the smaller gear drives the larger gear, the speed of rotation will be reduced and the torque will increase. If the larger gear drives the smaller gear, the speed of rotation will increase and the torque will be reduced.