| Your Results | Global Average | |
|---|---|---|
| Questions | 5 | 5 |
| Correct | 0 | 3.43 |
| Score | 0% | 69% |
A wedge converts force applied to its blunt end into force __________ its inclined surface.
opposite to |
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parallel to |
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along |
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perpendicular to |
The wedge is a moving inclined plane that is used to lift, hold, or break apart an object. A wedge converts force applied to its blunt end into force perpendicular to its inclined surface. In contrast to a stationary plane where force is applied to the object being moved, with a wedge the object is stationary and the force is being applied to the plane. Examples of a wedge include knives and chisels.
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?
work-energy theorem |
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Pascal's law |
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conservation of mechanical energy |
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mechanical advantage |
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.
The force exerted on an object due to gravity is called:
mass |
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potential energy |
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weight |
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density |
Mass is an intrinsic property of matter and does not vary. Weight is the force exerted on the mass of an object due to gravity and a specific case of Newton's Second Law of Motion. Replace force with weight and acceleration with acceleration due to gravity on Earth (g) and the result is the formula for weight: W = mg or, substituting for g, weight equals mass multiplied by 9.8 m/s2.
A fixed pulley has a mechanical advantage of:
1 |
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2 |
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0 |
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-1 |
A fixed pulley is used to change the direction of a force and does not multiply the force applied. As such, it has a mechanical advantage of one. The benefit of a fixed pulley is that it can allow the force to be applied at a more convenient angle, for example, pulling downward or horizontally to lift an object instead of upward.
An object's resistance to changes in direction is known as:
mass |
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inertia |
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kinetic energy |
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weight |
The more mass a substance has the more force is required to move it or to change its direction. This resistance to changes in direction is known as inertia.