Go Speedracer!! Go!!
Part 1
• Using metersticks and stopwatches,
record the time it takes for the racecar to
travel 3 meters.
• Record the time at 30 cm intervals in a
table containing both time and distance.
Distance (d): How far something
travels in changing position (total)
EX. I live 5 miles from NPHS. Where do I live?
Scalar Quantity
A quantity that
has magnitude
(size) only. No
direction.
Ex. Mass, time,
temperature
AVERAGE SPEED (S)
Def:
OR
*SCALAR
quantity
The total distance traveled
Time to travel distance
d
S=
Δt
*Where the
bar means average
and Δ means change
SI UNITS:
meters/second
OR m/s
*km/hr more common
British Engineering Standard:
feet/second
OR ft/s
Conversion
1 m/s = 3.6 km/h = 2.24 mi/h
1 mph = 1.609 km/hr = 0.447 m/s
*miles/hour (mph)
more common
*quick convert: mph ≈ twice m/s
Instantaneous Speed
Speed at a specific
instant in time
Usain Bolt holds the record for the 100m dash at 9.58 seconds.
Find his average speed in : a.) m/s b.) km/hr c.) mph
100 m/9.58 sec = 10.44 m/s
10.44 m/s X (7.2 km/hr) = 37.58 km/hr
( 2 m/s )
10.44 m/s X (4.5 mph) = 23.49 mph
(2 m/s)
Go Speedracer!! Go!!
Part 2
• Calculate the racecar’s average speed for
each interval and the entire trip.
• Use your data to plot a graph of the
position of the car versus time.
Complete “Investigating Travel in the Halls of NPHS”
Average Speed Analysis table.
*Don’t use rounded numbers (the
ones recorded in table)—use originals
for each speed unit!