Motion
why is it important to specify a reference point?
motion is relative
Provide the definition or formula for speed
How quickly an object changes location
distance/time
What is the definition or formula for acceleration
rate of change in velocity
change in velocity/change in time
The Indy 500 track is 4km in distance. What would a drivers distance and displacement be after 2 laps?
distance 8km 8000meters
displacement= 0
If there is a straight line on a position time graph what can be assumed about acceleration?
acceleration = 0
What is the difference between displacement and distance?
displacement is a vector, distance and location
What is the definition or formula for velocity?
the speed and direction of an object
displacement/time
what does negative acceleration mean?
acceleration (changing velocity) in a negative direction
A pitcher throws a ball 18 meters with a speed of 40m/s what was the time duration of the pitch?
speed= distance/time
time=distance/speed
18 m divided by 40 m/s = .45 seconds
What does a straight line indicate on a velocity time graph?
constant velocity
race track, loop, lap, start and finish in the same location
what are the units of velocity
meters/second m/s
What are the units for acceleration
m/s2
Look at the position time graph drawn on the board. What is the average velocity from 3 to 4 seconds?
60 m/s
What does acceleration look like on a velocity time graph?
curve
Displacement and Distance vector or scaler?
distance- scaler
displacement- vector
speed and velocity vector or scaler?
scaler- speed
vector- velocity
A car accelerates from a stop light at a rate of 2 m/s2 to a velocity of 50 m/s traveling east in 25 seconds. List the knowns and unknowns
Vi= 0
Vf= 50 m/s
a=2
t= 30s
d=?
Dr. Hotshot accelerates his porsche from 0 to 60 miles/hr in 4 seconds what is his acceleration? Give units (no need to convert miles)
a= v/t
a = 60mi/hr divided by 4 seconds = 15 mi/hr/s
what does the area underneath the slope on a velocity time graph represent?
displacement
An Uber eats driver drove 5 miles West from his home to pick up the order than 80 miles East to deliver the food. What is his net displacement?
30 miles East
A student walked home a distance of 500 meters in 3 minutes what is her velocity? (include correct units)
3 min = 10,000s
500meters/10,000s = 21.6 m/s
a child pedals their tricycle with an acceleration of 1.4 m/s/s, how long does it take to reach a speed of 2m/s?
time= a/v (a=v/t)
2m/s divided by 1.4 m/s/s = 1.43 s
Look at the velocity time graph on the board. What is the acceleration from 3-6 seconds?
acceleration = change in velocity divided change in time
vi= 10 m/s vf= 30 m/s
ti= 3s tf= 6s
30-10/6-3= 6.66 m/s2
Give a summary of the 5 problem solving steps for kinematic equations
1. sketch
2. knowns/unknowns
3. Formula
4. Solve
5. Reasonable? units? sig figs?