Frame of Reference
Unit Conversions
dtot, dnet, S, & v
rearrange eqxns & relationships btwn vars
graphs
random
100
What is the FoR? "the car is moving forwards?"
FoR: the earth / the tree
100
We're in school today from 8:30AM to 3:30PM. How many minutes is that?
7 hours (60 min / 1 hr) = 420 min
100
What is the distance the ant travels? What is his displacement?
distance: 20in
displacement: 14in East
100
S = dtot / Δt
Are S & dtot on same side or different sides of the division bar?
Does increasing distance increase or decrease speed?
increases speed. because they are on same side (top)
100
What time does the purple runner pass the green runner?
Where the lines intersect (4s,30m)
100
What year did Cars (the original one) come out?
2006
200
What is the FoR? "the trees are moving backwards?"
FoR: the car / the person
200
Convert 12 miles to km. (1 mi = 1.609km)
12mi (1.609km / 1 mi) = 19.3km
200
Caleb walks 6 meters East, and 8 meters South. What is his displacement? (Hint, draw out diagram)
a2 + b2 = c2
62 + 82 = c2
c = 10 meters SE (need direction)
200
S = dtot / Δt
If distance was 2 miles, but increases to 4 miles, how will that affect speed? (if the elapsed time remains constant)
Speed must double (S & dtot are on same side of the division bar, so change together)
200
What is the speed of the purple runner?
(40-0)/(5-1) = 40/4 = 10m/s
200
What is Mr. David's last name?
Wilson
300
According to purple's frame of reference, how fast is purple moving?
0m/s, because it's his own FoR
300
Convert 2 miles --> inches (1 mi = 5280 ft, 1 ft = 12 in). Show work with conversion ratios.
2 mi (5280 ft / 1 mi) (12 in / 1 ft) = 126,720 in
300
The ant's whole journey takes 70 seconds. What is his speed? (remember find distance first)
S = 20/70 = 0.29 in/s
300
S = dtot / Δt
If elapsed time was 1 hr, but increases to 3 hr, how will that affect S?
Decrease speed by 3x (because S and Δt are on opposite sides of division bar)
300
A runner starts a race at t = 0s. She runs 40 yards in 5 seconds. Make a graph: add title, label axes, plot points & draw slope, find equation of line.
300
What is Andy's last name?
Galbraith
400
From the purple's frame of reference, what is green's movement at the beginning of the race (t=0-1s)? what is green's movement at the end of the race (t=1-5s)?
don't need to give exact numbers, just describe "forwards" or "backwards"
according to purp, green is going forward, then going backwards.
400
convert 60 miles per hour --> m/s
(1 mi = 1.609 km, 1 km = 1000m, 1 hr = 3600s)
60mi/hr (1.609km / mi) (1000m / 1km) (1hr / 3600s)
= 60(1609) / (3600) = 26.8m/s
400
The ant's whole journey takes 70 seconds. What is his velocity? (remember find displacement first)
v = 14 / 70 = 0.2 in/s East
400
S = dtot / Δt
rearrange the equation for Δt
Δt = dtot / S
400
A runner runs a 40 yard dash in 8 seconds (after he starts running, not at t=0). The runner starts running 1.5 seconds after the camera starts recording (t = 1.5s). Figure out final point. Make a graph: add title, label axes, plot points & draw slope, find equation of line.
400
What are the names of my TAs? (100 points per TA, max up to 400 points)
Matthew (Mochi), Nathan, Lucas, Axcel, Mmasi, Xuan, Hasibah, Leyna