Term
| Newton's First Law of Motion |
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Definition
INERTIA
an object either is at rest or moves at a constant velocity, unless acted upon by an external force.
Objects keep doing what they are doing. |
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Term
| Newton's Sectond Law of Motion |
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Definition
ΣF=ma
Acceleration of a body is proportional to the net force acting on it and inversly proportional to the bodies mass. |
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Term
| Newton's Thrid Law of Motion |
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Definition
When one body exerts a force on a second body, the second body simultaneously exerts a force equal in magnitude and opposite in direction to that of the first body.
For every action, there is an equal and opposite reaction. |
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Term
A packing crate slides down an inclined ramp at constant velocity. Thus we can deduce that
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Definition
| a frictional force is acting on it. |
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Term
| You fall while skiing and one ski (of weight W) loosens and slides down an icy slope (assume no friction), which makes an angle θ with the horizontal. The force that pushes it down along the hill is |
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Definition
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Term
| A rope, tied between a motor and a crate, can pull the crate up a hill of ice (assume no friction) at constant velocity. The free-body diagram of the crate should contain |
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Definition
three forces.
F(tension), F(normal), F(gravity)
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Term
| If two identical masses, attached by a massless cord passing over a massless, frictionless pulley of an Atwood's machine (at different heights), are released |
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Definition
| the masses will not move. |
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Term
| A train consists of a caboose (mass = 1000 kg), a car (mass = 2000 kg), and an engine car (mass = 2000 kg). If the train has an acceleration of 5 m/s2, then the tension force in the coupling between the middle car and the engine car is |
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Definition
15,000 N
(mass(caboose)+mass(car))*a=F(tension)
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Term
| A decoration, of mass M, is suspended by a string from the ceiling inside an elevator. The elevator is traveling upward with a constant speed. The tension in the string is |
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Definition
Note: constant speed = no opposing acceleration to (9.8 m/s/s)
so ma=mg
Answer = equal to mg |
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Term
A toolbox, of mass M, is resting on a flat board. One end of the board is lifted up until the toolbox just starts to slide. The angle θ that the board makes with the horizontal for this to occur depends on the
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Definition
| coefficient of static friction, μ. |
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Term
our students perform an experiment by pulling an object horizontally across a frictionless table. They repeat the experiment on several other objects of different masses, always applying just enough force to produce the same acceleration. What does the graph (F/m) look like
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Definition
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Term
| An object is placed on an inclined plane. The angle of incline is gradually increased until the object begins to slide. The angle at which this occurs is θ. What is the coefficient of static friction between the object and the plane? |
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Definition
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Term
| A roller coaster car does a loop-the-loop. When it is upside down at the very top, What is the relationship between the F(normal) and the Weight (mg) |
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Definition
| The normal force and the weight are in the same direction. |
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Term
| A roller coaster car does a loop-the-loop. When it is right-side up at the very bottom, What is the relationship between F(normal) and Weight (mg) |
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Definition
| The normal force and the weight are in opposite directions. |
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Term
| A 0.5 kg (4.9 N) book rests on your desk. What is the reaction force to the 4.9 N weight (force) of the book? |
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Definition
| A 4.9 N force on the Earth. |
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Term
| You stand on a bathroom scale in an elevator accelerating upwards and it reads 200 Newtons. What force is the scale exerting on you? |
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Definition
| The scale exert a 200 N force on you. |
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Term
During the investigation of a traffic accident, police find skid marks 90 m long. They determine the coefficient of friction between the car's tires and the roadway to be 0.5 for the prevailing conditions. To find the speed of the car you must know
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Definition
the acceleration of the car.
The mass will cancel out of the equation. Review Chapter 4 in Giancoli.
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Term
An object moves left to right (right is positive) with speed decreasing at a constant rate and an accelertion of (+) or (-)
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Definition
| its acceleration is negative. |
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Term
A car pulls on a rope tied to a tree with a force of 1000 Newtons.What is the F(tension)
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Definition
| A car pulls on a rope tied to a tree with a force of 1000 Newtons. |
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Term
A 5 kg block and a 10 kg block slide down a frictionless incline. What is the relationship between their acceleration?
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Definition
| they both have the same acceleration. |
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Term
Two cardboard boxes full of books are in contact with each other on a frictionless table. Box H has twice the mass of box G. If you push on box G with a horizontal force F, then box H will experience a net force of
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Definition
A: 2/3 F
total a: F=3ma
a = F/(3m)
Find H: Fh=2ma
Fh= 2m(F/3m)
Fh = 2F/3 |
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Term
| what would the graph look like for The same horizontal force is applied to objects of different mass. |
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Definition
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Term
Four students perform an experiment by pulling an object horizontally across a frictionless table. They repeat the experiment on several other objects of different masses, always applying just enough force to produce the same acceleration. What does the graph look like
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Definition
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