| Your Results | Global Average | |
|---|---|---|
| Questions | 5 | 5 |
| Correct | 0 | 3.59 |
| Score | 0% | 72% |
The force amplification achieved by using a tool, mechanical device or machine system is called:
power |
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work |
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mechanical advantage |
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efficiency |
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.
| 3.5 | |
| 1 | |
| -5 | |
| 2 |
Mechanical advantage is resistance force divided by effort force:
MA = \( \frac{F_r}{F_e} \) = \( \frac{180 lbs.}{90 lbs.} \) = 2
Sam can do 50 ft. lb. of work in 2 minutes and 5 seconds. What would Sam have to do to increase his power output?
do the work in 3 minutes |
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do the work in 2 minutes |
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do 100 ft. lb. of work in 4 minutes 12 seconds |
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do 25 ft. lb. of work in 2 minutes 5 seconds |
Power is the rate of doing work or \(\frac{W}{t}\). To increase power, increase the work being done in the same amount of time or do the same amount of work in less time.
Which of the following is not a type of bridge?
cable |
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block |
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arch |
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truss |
The six basic bridge forms are beam, truss, arch, cantilever, cable, and suspension.
An inclined plane increases ___________ to reduce ____________.
distance, power |
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force, power |
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distance, force |
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force, distance |
An inclined plane is a simple machine that reduces the force needed to raise an object to a certain height. Work equals force x distance and, by increasing the distance that the object travels, an inclined plane reduces the force necessary to raise it to a particular height. In this case, the mechanical advantage is to make the task easier. An example of an inclined plane is a ramp.