Term
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Definition
| is commonly imagined as a push or a pull on some object, perhaps rapidly, as when we hit a tennis ball with a racket |
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Term
| is force a vector quantity and why |
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Definition
| yes it is, because we can control its magnitude and control its direction |
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Term
| give three examples of contact forces |
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Definition
| pull on a spring, pull a wagon & kick a football because they result from physical contact between two objects |
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Term
| corresponding forces are called field forces, why |
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Definition
the sun has a mass M and creates an invisible influence, and the earth has a mass m and interacts with the field of the sun
another example is electic forces that exert on each other
the known fundamental forces in nature are all field forces |
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Term
| list the known fundamental forces in decreasing strength |
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Definition
| nuclear forces between subatomic particles, electromagnetic forces between electric charges, the weak nuclear force (radio active decay), and the gravitational force between objects |
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Term
| Newton's first law of motion |
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Definition
an object moves with a velocity that is constant in magnitude and direction unless a non-zero net force acts on it
imagine pushing a book, the magnitude of the applied force is greater than the magnitude of friction |
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Term
| what is the net force on an object |
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Definition
| the vector sum of all external forces exerted on the object |
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Term
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Definition
| this is the tendency of an object to continue in its original state of motion |
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Term
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Definition
| a measure of the object's resistance to changes in its motion due to a force |
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Term
| if you apply a force twice as large, the acceleration doubles, what can we conclude from this statement |
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Definition
| the acceleration of an object is directly proportional to the net force acting on it |
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Term
| if the force applied to one block produces an acceleration of 2, then the acceleration drops to 1, when a second block is added, what can we conclude |
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Definition
| the acceleration of an object is inversely proportional to its mass |
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Term
| what is Newton's second law of motion |
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Definition
| the acceleration of an object is directly proportional to the net force acting on it, but inversely proportional to the mass of the object |
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Term
| how can you find accerlation |
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Definition
| the vector sum of all forces acting on the object divided by the mass of the object equals the acceleration |
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Term
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Definition
| this is the SI unit of force |
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Term
| an object can move even when no force acts on it |
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Definition
| true, an object in motion will stay in motion if no net force acts against it |
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Term
| if an object isn't moving, no external forces act on it |
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Definition
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Term
| if a single force acts on an object, the object accelerates |
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Definition
| true, as long as the force has more magnitude than the magnitude exert by friction |
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Term
| if an object accerlerates, a force is acting on it |
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Definition
| true, the acceleration is directly proportional to the net force acting on it |
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Term
| if an object isn't accelerating, no external force is acting on it |
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Definition
| false, inertia is the tendancy of an object to stay in motion in the absence of force |
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Term
| if the net force acting on an object is in the positive x-direction, the object moves only in the positive x-direction |
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Definition
| false, because the net force is the summation of x,y,z |
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