Chapter 3: Linear Motion Flashcards
Is credited with being the first to measure speed by considering the distance covered and the time it takes.
Galileo
The distance covered per unit of time.
Speed
The equation for speed.
Speed = Distance / Time
The speed at any instant.
Instantaneous Speed
The equation for average speed.
Average Speed = total distance covered ÷ time interval
If you’re ticketed for speeding which does the police officer write on your ticket your instantaneous speed or your average speed?
instantaneous speed
What is the equation for total distance covered?
Total distance covered = average speed x time interval.
What is the average speed of a cheetah that sprints 100 meters in four seconds?
Average speed = full distance covered ÷ by time interval.
25 m/s
What is the average speed of a cheetah that sprints 50 meters in two seconds?
Average speed = total distance covered ÷ time interval.
The speed of an object and its direction of motion; a vector quantity.
Velocity
A quantity in physics that has both magnitude and direction; examples are force, velocity, acceleration, torque, and electric and magnetic fields.
Vector quantity
Name six vector quantities.
Force, velocity, acceleration, torque, electric fields, and magnetic fields.
A quantity in physics such as mass, volume, time, and speed, that can be completely specified by its magnitude and has no direction.
scalar quantity
Steady speed
constant speed
Motion in a straight line at a constant speed. Means both constant speed and constant direction.
Constant Velocity
If either speed or direction change, what then will also change?
velocity
How quickly and in what direction velocity changes.
acceleration
What is the equation for acceleration.
Acceleration = change of velocity ÷ time interval
When somethings velocity is changing, we also say that it is…
accelerating
The key idea to find acceleration is…
change
What is the acceleration of a race car that was passed you at a constant velocity of 400 km/h?
Zero because its velocity doesn’t change
Motion under the influence of gravity only.
Free Fall
Equation used to specify how fast something is falling. Refers to speed or velocity.
v = gt
Equation used to specify how far something falls. Concerns the distance in which some thing falls.
d = 1/2gt²
Speed is how fast, velocity is how fast and in which direction, and acceleration is…
How fast how fast changes.
The rate at which velocity itself changes
acceleration
