KEY: Physics linear motion formulae
Δx
vf + vi
Δv
vavg = ───
vavg = ─────
aavg = ───
Δt
2
Δt
a = const.
vf = vi + at
xf = xi + v t
vf2 = vi2 + 2a(xf - xi)
NOT ON TEST! Tracker tips: 1) Load video 2) Set axes 3) Cleverly set scale 4) Hide axes & scale 5) Pick
point to track (not arms or legs!) 6) View graphs & statistics YOU need to see (i.e. change variables displayed)
1. Mike runs 20 m in 2.5 seconds starting from rest and accelerating uniformly.
a. What was his average speed?
8 m/s
b. If he ran north, what was his average velocity? 8 m/s N
c. What was his final speed?
16 m/s
d. What was his change in speed?
16 m/s
e. What was the magnitude of his acceleration?
6.4
m/s2
f. What was his acceleration?
6.4
North
2. If Carina skates down a ramp and accelerates from 2.0 m/s to 3.6 m/s, in 6.0 s, then how long is the ramp?
m/s2
16.8 m
3. Corine rolls a bowling ball 12.0 m down a lane. If this takes1.6 s, then how fast does she throw the ball?
7.5 m/s
4. Nick throws a baseball to his friend Mike. The ball leaves his hand going 20 m/s and decelerates uniformly
before reaching Mike going 16 m/s because of air resistance. If Mike is 45 m away then how long will the
ball be airborne?
2.5 sec
5. Katie rolls a ball down an inclined ramp to her friend Meg while her other friend is busy making copies. The
ball is initially rolled down the 12 m incline at 2.0 m/s and is going 5.0 m/s by the time it reaches Meg.
What is the rate of acceleration down this ramp?
0.875 m/s2
6. Rob and Tucker are driving to physics lecture to pursue their love of physics. On the way they need to
accelerate from 15 m/s to 25 m/s (55 mph). The on-ramp is 300 m long
a. What rate of acceleration is required?
0.67 m/s2
b. How fast will it take for them to go from 0 to 60 (27 m/s)?
40.3 sec
7. Jeff passes a puck to Casey. Casey is skating toward the net at 5.0 m/s and Jeff’s pass is going toward Casey
at 25 m/s. Casey begins 10 m ahead of Jeff.
a. How long does it take for the pass to reach Casey?
2.0 sec
b. How far does the puck travel in that time?
50 m
8. Mr. Williams tells Hannah and Claudia there is a box of Ghiradelli chocolates between them. Hannah and
Claudia are 50.0 m apart. Claudia is dressed for gym and can run 6.0 m/s and Hannah has fancy shoes that
slow her down and she can only run 2.5 m/s. If the candy is placed so they get there at the same time then
a. How much time elapses before they reach the chocolate?
5.9 sec
b. How far does Claudia run?
35.4 m
9. If Sarah and Allison are running in a race and Allison runs 6.0 m/s and Sarah runs 4.5 m/s, then how much
of a lead did Sarah have if it takes Allison 6.0 s to catch her?
10. What did you get for Vx in the video?