| Your Results | Global Average | |
|---|---|---|
| Questions | 5 | 5 |
| Correct | 0 | 2.95 |
| Score | 0% | 59% |
Which of the following will increase the mechanical advantage of this inclined plane?
shorten the ramp |
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increase the force acting at the blue arrow |
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lengthen the ramp |
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lower the force acting at the blue arrow |
The mechanical advantage (MA) of an inclined plane is the effort distance divided by the resistance distance. In order to increase mechanical advantage, this ratio must increase which means making the effort distance longer and this can be accomplished by lengthening the length of the ramp.
What defines the mechanical advantage of a first class lever?
position of the fulcrum |
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input force |
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output distance |
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output force |
A first-class lever is used to increase force or distance while changing the direction of the force. The lever pivots on a fulcrum and, when a force is applied to the lever at one side of the fulcrum, the other end moves in the opposite direction. The position of the fulcrum also defines the mechanical advantage of the lever. If the fulcrum is closer to the force being applied, the load can be moved a greater distance at the expense of requiring a greater input force. If the fulcrum is closer to the load, less force is required but the force must be applied over a longer distance. An example of a first-class lever is a seesaw / teeter-totter.
The principle of conservation of mechanical energy states that, as long as no other forces are applied, what will remain constant as an object falls?
kinetic energy |
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potential energy |
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total mechanical energy |
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acceleration |
As an object falls, its potential energy is converted into kinetic energy. The principle of conservation of mechanical energy states that, as long as no other forces are applied, total mechanical energy (PE + KE) of the object will remain constant at all points in its descent.
Assuming force applied remains constant, which of the following will result in more work being done?
moving the object with more speed |
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increasing the coefficient of friction |
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moving the object with more acceleration |
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moving the object farther |
Work is accomplished when force is applied to an object: W = Fd where F is force in newtons (N) and d is distance in meters (m). Thus, the more force that must be applied to move an object, the more work is done and the farther an object is moved by exerting force, the more work is done.
Friction between two or more solid objects that are not moving relative to each other is called:
dynamic friction |
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kinetic friction |
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static friction |
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gravitational friction |
Static friction is friction between two or more solid objects that are not moving relative to each other. An example is the friction that prevents a box on a sloped surface from sliding farther down the surface.