Physics Unit 1, Ch. 2- 1D Kinematics
speeding up
A boat is traveling west while accelerating to the west. Is the boat slowing down or speeding up?
distance
A quantity that refers to how much ground an object has covered
displacement
A straight line measured from the position the object starts to where the object ends
-9.81, downward
Acceleration due to gravity is _______ m/s2 and directed _____________
9.81m/s2
Free falling object's acceleration always equals.....
if velocity is positive, direction is positive. If velocity is negative, direction is negative.
On a Velocity vs. Time graph... How do you know if the line is moving in the positive or direction?
the line is downward sloping
On a Velocity vs. Time graph... how do you know if acceleration is negative?
the line is upward sloping
On a Velocity vs. Time graph... how do you know if acceleration is positive?
speeding up
if velocity and acceleration are in the SAME (+,+ or -,-) direction, is the object speeding up or slowing down?
object speeds up, velocity increases, a = -9.81m/s2
As an object falls downwards, what happens to the velocity? Acceleration?
v= 0m/s, a= 9.81 m/s2
At an object's highest point, what is the acceleration? What is the velocity?
velocity
Change in position divided by the time interval
When an object is being thrown up, velocity decreases. at the top of its path (highest point), the object briefly stops, changes direction, and v=0. As the object falls downward, the object speeds up and velocity increases. Throughout the entire process, acceleration stays at -9.81 m/s2
Describe the change in velocity of an object in free fall
There is no acceleration because velocity is constant. There's velocity in the positive direction.
Describe the motion in this graph.
the object is moving in the positive direction at a constant velocity, the object stops moving, object moves in positive direction at constant velocity, object stops moving, object moves in the negative direction at a constant velocity
Describe the motion in this graph.
velocity is changing, and the object is accelerating. The object is accelerating in the positive direction.
Describe the motion in this graph.
distance has only direction. Displacement has both magnitude and Direction.
Difference between Distance and Displacement?
Speed only has direction, velocity has both magnitude and direction
Difference between speed & Velocity?
delta x = xf- xi
Equation for Displacement
delta x / delta t
Equation for Velocity
add the amount of space covered
How do you calculate distance?
curved line
How do you know if an object is Accelerating on... Position vs. Time graph
slope is increasing/ decreasing, is a non zero value, or goes up/down
How do you know if an object is moving on a.. Position v. Time graph?
the line is above or below the x axis, but not on it
How do you know if an object is moving on a.. Velocity v. Time
the line switches from going up to down & vice versa
How do you know when an object changes direction on... Position vs. Time graph
when the crosses the x-axis and switches from positive to negative
How do you know when an object changes direction on... Velocity v. Time graph
slope is positive and moving in the positive direction. If slope is negative, the direction is negative
How do you know which way an object is moving on a Position v. time graph
if the line is above the x-axis, velocity and direction are positive. If the line is below the x-axis, velocity and direction are negative
How do you know which way an object is moving on a... Velocity v. Time graph
speed is how fast an object is moving and only deals with direction. Velocity indicates how fast an object is going and the direction
How does Speed and velocity differ?
accelerating but it is negative. The displacement decreases each second
If an object's velocity is Decreasing, then the object is...
acceleration is 0
If an object's velocity is constant, then...
accelerating
If an object's velocity is increasing, then the object is...
slowing down
If velocity and acceleration are in DIFFERENT (+, -) directions, is the object speeding up or slowing down?
if its motion or its velocity is changing
In general, how do you know if an object is accelerating?
no
Is an object with constant velocity accelerating?
displacement
The difference between an object's final & initial positions
acceleration
The rate at which velocity changes over time
free fall
The state of motion of an object facing under the sole influence of gravity
true
True or False Anytime an object's velocity changes, the object is accelerating
true
True or False? During Free Fall, the initial and final velocities are equal in magnitude
false
True or False? The time it takes for the object to travel upward is NOT equal to the time it takes the object to travel downward
true
True or False? There is acceleration whenever velocity is changing
true
True or False? Whenever successive displacements are changing, there is acceleration
meter
Unit for Displacement
meter
Unit for Distance
meter
Unit for position
m/s2 or km/hr2
Units for Acceleration
m/s or km/hr
Units for Speed
m/s or km/hr
Units for Velocity
delta x or delta y
Variable for Displacement
V
Variable for Velocity
a
Variable for acceleration
x, y,
Variables for Position
s
Variables for distance
object is moving in the positive direction with positive acceleration and is speeding up. Neither velocity or acceleration are constant.
What does Graph C show?
object is accelerating in the positive direction and is speeding up. Acceleration is changing, not constant. Velocity is not constant.
What does Graph D show?
the velocity is changing and the object is accelerating
What does a curved line mean on a Position vs. Time Graph?
object is moving left, downward, west, or south
What does negative Displacement, velocity, or Acceleration?
an object is moving right, east, upward, or north
What does positive Displacement, velocity, or Acceleration?
velocity
What does slope of a Position v. Time graph represent?
acceleration
What does slope of a Velocity v. Time graph represent?
the object is moving in the positive direction with constant, negative acceleration and is slowing down. Velocity positive and not constant.
What does this graph show?
the object is moving with constant, positive acceleration in the positive direction and is speeding up. Velocity is also positive.
What does this graph show?
velocity is constant and positive. there is zero acceleration because velocity is not changing
What does this graph show?
velocity decreases, acceleration slows down,
What happens when the velocity of an object is thrown upwards?
ag= -9.81 m/s2
What is the magnitude & direction of Acceleration for all objects in Free Fall
speed
Which equation is this?
constant acceleration
an ideal situation in which an object;s velocity is changing at a constant rate
position
an objects _____________ is its distance in the same direction from a reference point
the object is not moving
describe the motion in this graph.
with a positive or negative sign
how do we represent the direction of a 1D displacement?
rate of change
tells you how quickly or slowly a quantity changes as it passes
displacement
the change in position of an object
speed
the numerical value stating how fast an object travels
constant velocity
the object in motion is moving in a straight line at a constant speed
v
variable for speed