1. Day 1
UNIT 1 Motion Graphs x t
Lyzinski Physics

2. PHYSICS - Mechanics - Electricity - Magnetism - Optics - Waves
KINEMATICS
- Mechanics
A “description” of motion
- Electricity
DYNAMICS
- Magnetism
A study of what “causes”
motion
- Optics
- Waves

3. Day #1 * Distance * Speed * Unit Conversions * Scalars * d-t graphs

4. Definition Distance (d) – the length of the path
followed by an object.
* If an object’s path is straight, the distance is the length of
the straight line between start and finish.
** If an object’s path is NOT straight, the distance is the
length of the path if you were to “straighten it out” and
measure it the way you would measure the length of a
curved shoelace.
start
finish
start
finish

5. B C A
meters
Using the number line above, what would be the distance travelled if an object travelled from ….. 1m
- A to B
- A to C
- A to C and then back to A
- C to B, passing through A 4m
4m + 4m = 8m
4m + 1m = 5m

6. 4 yd B 12 yd 5 yd C A Sally and Timmy are at point A.
Sally walks directly to point C (taking the shortest path).
Timmy also takes a “shortest path”, but has to stop at point B for lunch first.
How much further has Timmy walked when he arrives?
4 yd

7. (or s=d/t) Definition Average Speed (s) – the distance
travelled during a time interval divided
by the elapsed time.
s = d/Dt
(or s=d/t)
we often abbreviate ”Dt” as “t”

8. s = d/t  t = d/s = (7mi)/(6mi/h)=1.17hB C A
miles
Larry walks from point B to point C, and then goes directly to point A. If he walks at an average speed of 6 mph, how long does the trip take him?
d = 3mi + 4mi = 7mi
s = 6 mi/h
s = d/t  t = d/s = (7mi)/(6mi/h)=1.17h

9. B C A km
Larry runs from point A to point B in 5 minutes and then proceeds to jog directly to point C, taking his time in 30 additional minutes. Find…
Larry’s average speed during the first portion of the trip.
The average speed during the second portion of the trip.
Larry’s average speed for the entire trip.
s = d/t = (1km)/(5min) = 0.2 km/min = 12 km/h
s = d/t = (3km)/(30min) = 0.1 km/min = 6 km/h
s = d/t = (4km)/(35min) = km/min = 6.86 km/h

10. Unit Conversions Convert 5 km/h to m/s. Convert 60 ft/s to mi/h.
Convert 30 mi/h to m/min!!!!

11. Definition distance speed time
Scalar – a quantity that has a magnitude
only, no direction.
* YES, scalars can have units.
** What scalars have we learned about thus far?
___________ ____________ ___________
distance
speed
time
I thought time could march backward?

12. d-t graphs E F D C B A Constant speed Speeding UP
Constant Speed (faster!)
Slowing Down
At rest
t (sec)
d (m) B C E A D F
120
100 50 30

13. sAB = rise/run = (30-0m) / (10-0s) = 3 m/s
t (sec)
d (m) B C E A D F
120
100 50 30
SLOPE
Speed on a d-t graph can be found by taking the _______________.
sAB = rise/run = (30-0m) / (10-0s) = 3 m/s
sCD = rise/run = (100-50m) / (20-15s) = 10 m/s

14. 1 Open to in your GREEN packet 520 – 170yd = 350 yd (approximately)
d-t graphs CANNOT have sharp points
NOTHING CAN STOP INSTANTANEOUSLY!!
minutes
520 – 170yd = 350 yd (approximately)

15. HOMEWORK
Check out your Unit 1 Schedule … Day #1 We will “try” to follow it night by night.