| Your Results | Global Average | |
|---|---|---|
| Questions | 5 | 5 |
| Correct | 0 | 3.02 |
| Score | 0% | 60% |
The science that deals with motion and the forces that produce motion is called which of the following?
engineering |
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aeronautics |
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mechanics |
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physics |
Mechanics deals with motion and the forces that produce motion.
Which of the following represents the force a surface exerts when an object presses against it?
mass |
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normal force |
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friction |
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counter force |
Normal force (FN) represents the force a surface exerts when an object presses against it.
The force exerted on an object due to gravity is called:
potential energy |
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mass |
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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.
Torque involves a perpendicular force applied to a lever arm that moves around a center of rotation. Increasing the length of the lever arm will do which of the following?
increase applied force |
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decrease torque |
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decrease applied force |
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increase torque |
Torque measures force applied during rotation: τ = rF. Torque (τ, the Greek letter tau) = the radius of the lever arm (r) multiplied by the force (F) applied. Radius is measured from the center of rotation or fulcrum to the point at which the perpendicular force is being applied. The resulting unit for torque is newton-meter (N-m) or foot-pound (ft-lb).
Collinear forces:
act along the same line of action |
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are unrelated to each other |
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pass through a common point |
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act in a common plane |
Collinear forces act along the same line of action, concurrent forces pass through a common point and coplanar forces act in a common plane.