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definitions
definitions
defintions
questions
N.J ask practice
100
what is acceleration
a change in an objects speed or direction
100
what is inertia
the tendency of objects to keep doing what they are doing
100
what is newton's third law of motion
for every action, there is an equal and opposite reaction
100
If you hit the home run in space, what would happen
The baseball will keep moving in outer space acted by another force
100
Which of the following is an example of contact force
Friction
200
what is contact force
a force that must touch an object to change its speed and/or direction
200
what is net force
the amount by which the opposing forces acting on an objects are unequal
200
what is non-contact fore
a force that acts on an object to change its speed or direction from the distance.
200
Suppose that Sharon rides her bike at a speed of 10 m/s. As she rides up a hill, her speed will decreases to 5 m/s. Is her acceleration positive or negative
negative b/c she against the force of gravity
200
In which situation are the forces acting on the objects balanced?
A hot-air balloon rises at a constant speed
300
what is a force
a push or pull that causes something to change its motion
300
what is newton
the metric unit used to measure force or weight
300
what is normal force
the force that pushes up to support the weight of an object.
300
now, suppose Sharon rides her bike down the street in 20 sec. During this time, her speed remains constant at 5 m/s. What is the value of her acceleration during this time?
Speed is 0 meters per sec. b/c she is going at a constant speed.
300
The net force acting on an object in ON. Which of the following best describes the motion of the object.
The object's motion is not changing
400
what is friction
a force that occurs when two things move past each other and rub together
400
what is newton's first law of motion
if the forces acting on an objects are balanced, the object will continue doing what it is doing
400
Gabe kicked a soccer ball across a field. The ball rolled for a while but eventually stopped. If Newton's first law is true, it seems that the ball Gabe kicked should continue rolling forever, Whty does the ball stop?
Friction from the ground makes the ball stop rolling.
400
Give an example of a situation in which you apply a force to something and it does the following - Goes faster
car pushes on the gas pedel
400
Which of the following best describes the force that the car exerts on Sean.
The same amount as Sean ecerts
500
what is gravity
a force that acts without physical contact to pull two objects toward each other
500
what is newton's second law of motion
the acceleration of an object is related to the net force acting on it and the mass of the object
500
Suppose you are playing base ball and hit a home run. What forces slow down the ball while it is in motion?
Friction/gravity slows baseball while in motion
500
Goes slower
when the car presses on the brake
500
Which force has the greatest influence on the structure of solar systems and galaxies
Gravity