| Your Results | Global Average | |
|---|---|---|
| Questions | 5 | 5 |
| Correct | 0 | 3.33 |
| Score | 0% | 67% |
On Earth, acceleration due to gravity (g) is approximately __________.
6.67 x 10-11 m/s2 |
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1 m/s |
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1 m/s2 |
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9.8 m/s2 |
Newton's Law of Univeral Gravitation defines the general formula for the attraction of gravity between two objects: \(\vec{F_{g}} = { Gm_{1}m_{2} \over r^2}\) . In the specific case of an object falling toward Earth, the acceleration due to gravity (g) is approximately 9.8 m/s2.
The principle of moments defines equilibrium in terms of:
torque |
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power |
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speed |
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energy |
According to the principle of moments, you can maintain equilibrium if the moments (forces) tending to clockwise rotation are equal to the moments tending to counterclockwise rotation. Another name for these moments of force is torque.
The mass of an object correlates to the size of the object but ultimately depends on:
the object's density |
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the object's weight |
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the object's potential energy |
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gravity |
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.
Which of the following is not a type of bridge?
arch |
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cable |
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truss |
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block |
The six basic bridge forms are beam, truss, arch, cantilever, cable, and suspension.
Which of these will have the most impact on the kinetic energy of an object?
its mass |
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its weight |
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its speed |
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its direction |
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.