| Your Results | Global Average | |
|---|---|---|
| Questions | 5 | 5 |
| Correct | 0 | 2.84 |
| Score | 0% | 57% |
| None of these is correct | |
| 24 | |
| 40 | |
| 320 |
The work done by the sum of all forces acting on a particle equals the change in the kinetic energy of the particle. This defines which of the following?
Pascal's law |
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conservation of mechanical energy |
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mechanical advantage |
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work-energy theorem |
The work-energy theorem states that the work done by the sum of all forces acting on a particle equals the change in the kinetic energy of the particle. Simply put, work imparts kinetic energy to the matter upon which the work is being done.
What type of load doesn't create specific stress points or vary with time?
static uniformly distributed load |
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impact load |
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non-uniformly distributed load |
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concentrated 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.
The mechanical advantage of a wheel and axle is equal to the:
ratio of the diameters of the wheels |
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difference in the lengths of the axles |
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length of the axle |
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difference in the diameters of the wheels |
A wheel and axle uses two different diameter wheels mounted to a connecting axle. Force is applied to the larger wheel and large movements of this wheel result in small movements in the smaller wheel. Because a larger movement distance is being translated to a smaller distance, force is increased with a mechanical advantage equal to the ratio of the diameters of the wheels. An example of a wheel and axle is the steering wheel of a car.
A truck is using a rope to pull a car. Tension in the rope is greatest in which of the following places?
in the middle |
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near the car |
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near the truck |
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tension is equal in all parts of the rope |
Tension is a force that stretches or elongates something. When a cable or rope is used to pull an object, for example, it stretches internally as it accepts the weight that it's moving. Although tension is often treated as applying equally to all parts of a material, it's greater at the places where the material is under the most stress.