Chapter 3 Summary
• Every object in the Universe is moving relative to some other object.
• The motion of an object can be very different for people in different reference frames.
• Average speed is figured by taking the total distance that you traveled and dividing it by the total time the trip took.
• Instantaneous speed is how fast an object is going at any particular instant.
• Graphing data is a very useful way to analyze the relationships between the variables.
• The slope of the line at any one point on a position vs. time graph is the instantaneous speed of the object at that time.
• When describing the velocity of an object, the direction the object is traveling is required.
• Acceleration describes how quickly velocity changes.
• Like velocity, it is essential to provide the direction when describing acceleration.
• In physics, 'accelerating' can mean three things: speeding up, slowing down, or changing direction (turning).
• Average acceleration is figured by taking the change in the object's velocity and dividing it by the time interval.
• When air resistance is ignored, all objects near the surface of the Earth fall at the same rate regardless of their mass.
• On Earth, the free fall acceleration is 9.8 m/s/s. This is usually written as g.
Definitions
• Speed – the rate at which an object's distance from a given point changes.
• Velocity – speed in a given direction.
• Graph - A visual representation of a quantitative relationship. e.g. the relationship between the distance an object travels and the time it takes for the trip.
• Acceleration – the rate at which velocity changes.
• Free fall – the motion of an object that is falling solely under the influence of gravity. i.e. there is no friction or air resistance.
Equations
• Average Speed = change in distance / change in time = Δd/Δt
• Acceleration = change in velocity / change in time = Δv/Δt
• Equations to use when object is traveling at a constant speed or velocity:
o V = Δd/Δt
• Equations to use when object is accelerating:
o a = (vf - vi)/Δt
o d = vit + 1/2at2
Units
• meters/second (m/s) – typical unit used to describe speed or velocity
• meters/second/second (m/s/s) – typical unit used to describe acceleration
• The motion of an object can be very different for people in different reference frames.
• Average speed is figured by taking the total distance that you traveled and dividing it by the total time the trip took.
• Instantaneous speed is how fast an object is going at any particular instant.
• Graphing data is a very useful way to analyze the relationships between the variables.
• The slope of the line at any one point on a position vs. time graph is the instantaneous speed of the object at that time.
• When describing the velocity of an object, the direction the object is traveling is required.
• Acceleration describes how quickly velocity changes.
• Like velocity, it is essential to provide the direction when describing acceleration.
• In physics, 'accelerating' can mean three things: speeding up, slowing down, or changing direction (turning).
• Average acceleration is figured by taking the change in the object's velocity and dividing it by the time interval.
• When air resistance is ignored, all objects near the surface of the Earth fall at the same rate regardless of their mass.
• On Earth, the free fall acceleration is 9.8 m/s/s. This is usually written as g.
Definitions
• Speed – the rate at which an object's distance from a given point changes.
• Velocity – speed in a given direction.
• Graph - A visual representation of a quantitative relationship. e.g. the relationship between the distance an object travels and the time it takes for the trip.
• Acceleration – the rate at which velocity changes.
• Free fall – the motion of an object that is falling solely under the influence of gravity. i.e. there is no friction or air resistance.
Equations
• Average Speed = change in distance / change in time = Δd/Δt
• Acceleration = change in velocity / change in time = Δv/Δt
• Equations to use when object is traveling at a constant speed or velocity:
o V = Δd/Δt
• Equations to use when object is accelerating:
o a = (vf - vi)/Δt
o d = vit + 1/2at2
Units
• meters/second (m/s) – typical unit used to describe speed or velocity
• meters/second/second (m/s/s) – typical unit used to describe acceleration