Kinematics Flashcards
The location of an object in relation to some “reference point”
Position
If an object is not accelerating, you can be absolutely positive that it is experiencing ________________.
Zero Net Force
What would be the net force upon this object?
30 N to the right.
The symbol for time
t
In linear motion, the “+” and the “-“ symbols are used to show what?
Direction
True/False
This fighter jet is in “Free Fall.”
False.
This fighter jet has more forces acting upon it than just gravity. It is experiencing the following forces:
- Gravity
- “Lift” (from the air on the wings)
- “Thrust” (generated by the afterburners)
What is meant by the acronym:
A.U.T.O.graph
When we look at graphs, we will always think about:
A - the axes
U - the units
T - the trace
O - the origin
Newton’s Third Law
For every action, there is an equal and opposite reaction.
Newton’s Second Law
A = F/M
(Acceleration = Force divided by Mass)
Acceleration
That rate at which you change your velocity.
Example:
Every second, he was going 5mph faster than the second before.
A quantity that has both magnitude and direction is called a _______________.
Example:
Forces are ________ because if you push or pull on something, there is a magnitude (size) of your push, and there is always a direction of your push.
Vector
What would be the net force upon this object?
10 N to the left.
What would be the net force upon this object?
1 Newton to the right.
Velocity at clock reading = t
<span>v</span>t
A point or exact location that can be used to help describe the location of some other point or object.
Reference Point
Constant Speed
Not speeding up or slowing down
A letter written smaller and below the rest of the writing.
<span>v</span>t
Here the “ t “ is subscripted
Subscript
Newton’s Second Law
A = F/M
(Acceleration = Force divided by Mass)
Another way of saying that someone is accelerating in such a fashion that each second they were going 7 meters per second faster than the second before?
Acceleration = (7 m/s) / s
or
7m/s2
Air Friction
The force impeding the motion of an object traveling through the air.
In motion along a line, what is the difference between the following two “velocities?”
17 m/s
-17 m/s
The objects are traveling at the same speed, but in opposite directions.
In linear motion, we can use plus and minus to represent different directions.
Reference Point
A point or exact location that can be used to help describe the location of some other point or object.
Mass
How much “stuff” there is in an object.
(or how much matter)
(each added atom or molecule adds mass)
When we refer to the “trace” on a graph, we are talking about …
The best fit line or curve on the graph.
Slope
The angle of a line on a graph
More mass means more ___________.
Inertia
Net Force
The overall force acting upon an object.
True/False
The soccer ball shown in the picture is in “Free Fall.”
True.
It doesn’t matter if the ball is going up, down, or sideways. As long as the only force acting upon the ball is gravity, it is in “Free Fall.”
The size of the force of air friction is dependant upon
______________
and
_______________
The size and shape of an object
and
The speed at which the object is moving relative to the air.
This is called a
Motion Map
Scaler
A quantity that has a magnitude (size) but no direction.
Examples:
Temperature. 78 degrees tells you how “big” the temperature is, but there is no direction to 78 degrees.
In order to describe the position of an object, you must always refer to a ___________ _____________.
Reference Point
(or reference object)
Speed
How fast an object is traveling.
(Direction is not important)
Average Speed
A single speed that can be used to represent an object’s speed during a period of time, even if the object is changing speeds.
Is velocity a vector or a scaler?
Velocity is a vector.
It has both magnitude (size) AND direction.
Example:
Her velocity was 30 mph north.
Which object is moving faster?
A car going +10 mph
A moped going - 10 mph
Neither.
They are both going the same speed, but in different directions.
<span>x</span>0
Position at clock reading = zero
Inertia
VERY close in meaning to “mass”
BUT
Inertia is usually used when you are talking about stopping a moving object or making a stationary object start moving.
True/False
The entire time between when this cannonball
leaves the cannon until it hits the ground,
the cannonball is in
“Free Fall.”
True.
Once it leaves the cannon, the only force acting upon the cannonball is gravity.
x
the symbol for position
(X marks the spot)
Velocity/Time graph
A motion graph with time on the horizontal axis and velocity on the vertical axis.
a
The symbol for acceleration
Vector
A quantity that has both magnitude and direction.
Example:
Forces are vectors because if you push or pull on something, there is a magnitude (size) of your push, and there is always a direction of your push.
Position at clock reading = “t”
<span>x</span>t
The angle of a line on a graph
Slope
<span>v</span>t
Velocity at clock reading = t
the symbol for distance
d
Displacement
How far you are from where you started, and in what direction.
How big something is.
Magnitude
What mathematical calculation would you do to determine the net force upon the skydiver shown here?
Net Force = (Force of Gravity) - (Force of Air Friction)
That rate at which you change your velocity.
Example:
Every second, he was going 5mph faster than the second before.
Acceleration
The symbol for acceleration
a
Change in Momentum and ________ mean the same thing
Impulse
Gravity
A force between any two objects with mass
What would be the net force upon this object?
30 N to the right
All of the red lines are ____________ to the red curve.
“Normal”
(In physics, “normal” means “perpendicular to”)
Velocity
The speed and direction an object is travelling.
How fast an object is going at an instant in time. It is what is shown on the speedometer of a car.
Instantaneous Speed
What would be the net force upon this object?
10 Newtons to the left.
Any object experiencing zero net force will ALWAYS have _______________
Zero Acceleration
When they describe the “top velocity” of a type of airplane, the reference object they would typically use would be what?
The air the plane is flying in.
<span>v</span>0
Velocity at clock reading = zero
Velocity at clock reading = zero
<span>v</span>0
Which object is moving the fastest?
A
The steepest line on a position/time graph represent the fastest moving object.
(A is moving the opposite direction from B and D)
In linear motion, how will we show the direction an object is travelling?
With a “+” sign or a “-“ sign.
The plus would mean one direction, and the minus would mean in the exact opposite direction.
Is “speed” a scaler or a vector?
It is a scaler. Speed has a magnitude (size) but no direction.
Example: 50 mph.
Which object is not moving?
C
(did you remember to look at the axes?)
Look carefully at the following graph. Does this show and object that is moving or standing still.
Linear Motion
Motion along a line
Touch
Gravity
Friction
The three things we often think about when we are looking for forces.
A quantity that has a magnitude (size) but no direction.
Examples:
Temperature. 78 degrees tells you how “big” the temperature is, but there is no direction to 78 degrees.
Scaler
In Newton’s Third Law, which happens first, the action or the reaction.
Neither!
The “action” and “reaction” forces always happen at the exact same time.
Magnitude
How big something is.
Subscript
A letter written smaller and below the rest of the writing.
<span>v</span>t
Here the “ t “ is subscripted
d
the symbol for distance
If you say a ball is 30 feet up, what would typically be your reference point.
The ground below the ball.
(The ball would be 30 feet away from the reference point or ground in this case)
Tension
A force exerted by a string or rope.
the symbol for velocity
v
What would the net force be upon this object?
2 N to the right
acceleration / time graph
A motion graph with time on the horizontal axis and acceleration on the vertical axis.
What would be the net force upon this object?
100 Newtons upward
In linear motion, the difference between
-55 mph
and
+55 mph
is?
Direction only
When you describe the velocity of a car, your typical reference object would be what?
The surface of the road beneath the car.
v
the symbol for velocity
The study of motion
Kinematics
Distance
How far you have travelled.
In physical science the word “Normal” means
Perpendicular.
A single speed that can be used to represent an object’s speed during a period of time, even if the object is changing speeds.
Average Speed
In order to describe the velocity of an object, you must always refer to a ___________ _____________.
reference object
Position/Time graph
A motion graph with “time” on the horizontal axis and “position” on the vertical axis.
This graph shows the motion of 4 objects.
Instantaneous Speed
How fast an object is going at an instant in time. It is what is shown on the speedometer of a car.
Reference object
An object that can be used as a reference for both position and for velocity.
Position at clock reading = zero
<span>x</span>0
Another way of saying that someone is accelerating in such a fashion that each second they were going 8 mph faster than the second before?
Acceleration = (8 mph) / second
The formula for calculating the slope of a line.
Slope = rise/run
t
The symbol for time
How fast an object is traveling.
(Direction is not important)
Speed
Kinematics
The study of motion
The blue line could also be consider to be ______________ to the red surface
“Normal”
(In physics, “normal” and “perpendicular” mean the same thing)
In physics, the word “Impulse” means…
Change in Momentum
Slope = rise/run
The formula for calculating the slope of a line.
What is the formula for calculating momentum?
Momentum = Mass x Velocity
<span>x</span>t
Position at clock reading = “t”
Position
The location of an object in relation to some “reference point”
Newton’s First Law
Objects in motion stay in motion
Objects at rest stay at rest
If its moving, it will keep moving in a straight line, at the same velocity, FOREVER, unless acted upon by a net force.
the symbol for position
x
Acceleration = (8 mph) / second
Another way of saying that someone is accelerating in such a fashion that each second they were going 8 mph faster than the second before?
True or False
This motorcycle rider is in “Free Fall.”
True.
Once he goes off the jump, the only force acting upon him is the force of gravity. (Until he lands of course)
“Free Fall”
When the ONLY force acting upon an object is gravity.
This can be after an object is dropped.
It can also be after an object is thrown up.
It can even be after an object is thrown sideways.
In all these situations, the only force acting upon the object is gravity.
In which direction would the net force be upon this object?
To the left.
Acceleration can mean….
Speeding up
Slowing down
or
Turning
(Basically, anything you could feel while you were in a car would indicate acceleration)
What control or controls in a car is often used to cause the car to accelerate?
Gas Pedal
Brakes
Steering Wheel
(Remember, an acceleration can mean speeding up, slowing down, or turning)
You walk all the way around a typical high school track. Its about 400 meters.
Your Distance = ___________
Your Displacement = _____________
Your Distance = ___\_400-m______\_
Your Displacement = ___\__0-m\________
Distance is how far you travel.
Displacement is how far you end up from the starting point.
You are about to go outside to take measurements necessary to calculate your top running speed. What measurements would you need to take.
Distance
and
Time
(because S = d/t )
What is the formula for finding
Average Speed
What quantity is this device used to measure?
Time
What quantity is this device used to measure?
Volume
What quantity is this device used to measure?
Length
What quantity is this device used to measure?
Mass
(Note, mass is different than weight)
Scales measure weight
Balances measure mass
When we make a motion graph, what variable will ALWAYS be on the horizontal axis?
Time
(Even if time is the dependent variable, we will always put it on the horizontal axis in motion graphs.)
Is displacement a vector or a scalar?
Displacement is a vector. It has both magnitude and a direction.
Is the following a description of a distance or a displacement?
He travelled 20 miles North.
Displacement
(Magnitude = 20 miles)
(Direction = North)
Is the following a description of a distance or a displacement?
He traveled 30 meters.
Distance
It has no direction, so it cannot be a displacement.
True or false.
This object is moving at a constant speed.
False
( I guess zero is a constant speed, but it is not really moving, is it. It just stays at a position of 8 meters from the reference point)
30 meters is a distance, so its a scalar quantity.
If you add a direction so it reads
30 meters north, then it becomes
_______________ which is a ______________
If you add a direction so it reads
30 meters north, then it becomes
displacement which is a vector.
Time
Vector Quantity or not?
Not
3 seconds does not have a direction.
No direction, not a vector.
Distance
Vector Quantity or not?
Not
25 meters does not have a direction.
No direction, not a vector.
Temperature
Vector Quantity or not?
Not
37 degrees does not have a direction.
No direction, not a vector.
Speed
Vector Quantity or not?
Not
50 mph does not have a direction.
No direction, not a vector.
Velocity
Vector Quantity or not?
Vector Quantity
50 mph - North has both magnitude (50) and direction (North).
So, its a vector or vector quantity.
Force
Vector Quantity or not?
Vector
50 newtons downward has both magnitude (50) and direction (downward).
So, its a vector or vector quantity.
Acceleration
Vector Quantity or not?
Vector
- 5 m/s2 has both magnitude (5) and direction (negative).
So, its a vector or vector quantity.
The definition of “Displacement” is “how far you are from the reference point and in what direction.”
Displacement can also often be thought of as:
How far you are from where you started. (and in what direction)
“Uniform Linear Motion”
is just a physicsy way of saying….
“Moving in a straight line at a steady speed.”
What is the picture we use to remember the formula triangle shown?
This is Newton’s Second Law ( Fnet = ma )
What is the picture we use to remember the formula triangle shown?
What is the picture we use to remember the formula triangle shown?
What is the picture we use to remember the formula triangle shown?
Object “A” has a velocity of -5m/s.
Object “B” has a velocity of -3m/s.
Object “C” has a velocity of 0 m/s.
Which object is moving the fastest?
Object A is moving the fastest.
(Both objects are moving in the negative direction. Object “A” is moving at 5m/s, object “B” is only moving at 3m/s. Object “C” isn’t even moving, so it is pretty much going the slowest.)
Which of the following velocities represents the object travelling most slowly.
Car 1 is traveling at -40 mph
Car 2 is traveling at 0 mph
Car 3 is traveling at +20 mph.
Car 2 is traveling most slowly. (It is not even moving)
(Car “1” is traveling the fastest, even if it is moving in the negative direction)
True or False
“An object in equilibrium must be moving.”
FALSE
(An object in equilibrium could be either stopped or moving with a constant velocity)
True or False
“An object in equilibrium cannot be moving.”
FALSE
(An object in equilibrium could be either stopped or moving with a constant velocity)
