kinematics unit 1 Flashcards
What is displacement?
The final position minus the initial position (change in position or deltaX=xf-xi ) - VECTOR
What is distance?
The length of the path taken by an object - SCALAR
What is velocity?
The instantaneous rate of change in displacement - VECTOR (change in displacement over time)
What is speed?
The total distance over the total time it takes - SCALAR
What is acceleration?
The rate of change in velocity, speeding up or slowing down? (change in v/t) - VECTOR
In a position or displacement over time graph, what is happening to an object if given a curved upward line and what does it represent?
The object is moving along a linear path with an increasing velocity, representing its motion. (draw a tangent line to the curved line and find its slope)
In a position or displacement over time graph, what does the slope represent?
The velocity
In a velocity over time graph, what does the slope represent?
The acceleration
What can we mostly assume about acceleration
It’s usually constant
In a velocity over time graph, what does the area underneath the curve/line represent?
The position/displacement
In an acceleration over time graph, what does the area underneath the curve/line represent?
The velocity
What is free-fall?
When an object is moving in air under the gravitational force. The velocity increases due to an acceleration of 9.81m/s/s
What happens when you throw an object upwards?
The velocity decreases due to the downwards acceleration of gravitational force. It comes a temporary stop then falls back downwards with same magnitude as going up.
What happens to an object speeding up but decelerating?
Velocity is increasing. Acceleration is decreasing (due to negative acceleration)
What happens when an object is slowing down and accelerating?
Velocity is decreasing (-). Acceleration is increasing. (+)
What is 2-D motion?
Projectile motion, with two different vector components: X and Y. The gravitational force is always downwards. Typically the Vy gradually decreases then after reaching a value of zero at the max point, becomes negative pointing downward but increasing in magnitude. Vx does not change magnitude since no acceleration.
ONLY Vy CHANGES DUE TO G (Vertical component.
Vx NEVER CHANGES
When an object falls off a cliff, what is happening to the velocity and acceleration?
Vx does not change in magnitude but points right.
Vy increases while pointing downwards due to Fg.
What condition are all 3 kinematics equations provided on the formula sheet based upon?
Acceleration is CONSTANT, both DIRECTION AND MAGNITUDE.
What is the fourth equation NOT provided and what does it represent?
Xf-Xi=1/2(Vi+Vf)t
Represents the area in a velocity time graph, where the area is in the shape of a trapezoid
