Chapter 2: Kinematics in 1D Flashcards
What is the equation to find displacement?
ΔX = X - Xo
What does ΔX mean?
Displacement
What does X mean regarding the displacement equation?
Final distance
What does Xo mean regarding the displacement equation?
Initial distance
What is the difference between distance and displacement?
Distance is the overall amount traveled, while displacement is the amount between the starting and finishing point.
For example, a swimmer does 6 laps in a 50m pool. Their DISTANCE is 300m but their DISPLACEMENT is 0m.
What is the equation for average velocity?
Vav = ΔX / Δt
What does Vav mean?
Average velocity
What does Δt mean?
Elapsed time
How do you find Δt?
Δt = t - to
What does t in the elapsed time equation represent?
Final time
What does to in the elapsed time equation represent?
Initial time
Velocity is a vector. How is it’s direction shown?
Through +/- signs
Usually, Vav has an arrow written above the V. Why is this not the case in 1 dimension?
The arrow shows the direction, but in 1 dimension the +/- sign shows direction
What is the average acceleration equation?
Aav = ΔV / Δt
What does Aav mean?
Average acceleration
What does ΔV mean?
Change in velocity
How do you find ΔV?
V - Vo
What does V mean in the changei n velocity equation?
Velocity
What does Vo mean in the change in velocity equation?
Initial velocity
If you have an object and the velocity and acceleration are the same sign (++ / –) are you speeding up or slowing down?
A) Speeding up
B) Slowly down
C) Depends on the sign
A
A) Speeding up. If the signs match, you are speeding up. + or - do not show “speed” they show DIRECTION
If you have an object where the acceleration and velocity are opposite signs (+- / -+) are you speeding up or slowing down?
A) Speeding up
B) Slowing down
C) They cancel each other out
B
B) Slowing down. The signs just show direction not speed.
What are the 5 variables of constant acceleration?
a = acceleration vector
ΔX = displacement vector
Vo = initial velocity vector
V = final velocity vector
t = time (not a vector)
How many of the 5 variables do you need to solve for constant acceleration?
3
What are the 4 equations for constant acceleration?
1) V = Vo + at
2) ΔX = 1/2 (Vo+V)t
3) V^2 = Vo^2 + 2aΔX
4) ΔX = Vot + 1/2at^2