Conversion Factors
Write a conversion factor (in the form of a fraction) that shows how many centimeters are in a meter.
1 m / 100 cm
or
100 cm / 1 m
The measurement system used by scientists
Metric or SI
Write all three forms of the speed equation.
d = st
s = d/t
t = d/s
Write the acceleration equation.
(Final speed - initial speed) / time
In a distance time graph, what is on the x-axis and what is on the y-axis?
x-axis = Time
y-axis = Distance
Yesterday, Victoria ran 1600 m. Use conversion factors to show how many kilometers this is.
1600 m x 1 km / 1000 m = 1.6 km
a) The length between two points
b) An object used to determine if another object is in motion
a) Distance
b) Reference point
Naima takes 8 seconds to walk west from Science to Social Studies (a distance of 2.5 meters).
a) What is her average speed during that time?
b) What is her average velocity?
a) 3.2 m/s
b) 3.2 m/s west
What is the acceleration of the object in the table below?
TIME (s) SPEED (m/s)
0 0
1 15
2 30
3 45
15 m/s2
What does the slope of a distance-time graph represent?
Speed
One pencil costs 10 cents. Use conversion factors to show how many DOLLARS it costs to buy 7 pencils.
7 pencils x 10 cents / 1 pencil = 70 cents
70 cents x 1 dollar / 100 cents = 0.70 dollars
a )The amount of distance covered per unit of time
b) The amount of distance covered per unit of time, with direction included
a) speed
b) velocity
True or false: An object's instantaneous speed must always be the same as its average speed overall. Explain your answer.
False! An object may speed up or slow down during its motion.
If the object below were to travel for 6 seconds and accelerate at the same rate the whole time, what would its speed be at 6 seconds?
What is the acceleration of the object in the table below?
TIME (s) SPEED (m/s)
0 0
1 15
2 30
3 45
90 m/s
a) In the graph on the screen, what time did the person first come to a stop?
b) How long did they stop for (from B to C only)?
a) 5 hours
b) 3 hours
Nako can run 10 miles in one hour. Use conversion factors to show how many miles he can run in one second.
0.17 miles / 1 min x 1 min / 60 s = 0.003 miles
The rate of change of velocity
Acceleration
How much time does it take a car to drive 200 miles if it goes at a speed of 65 miles per hour?
3.07 hours
Which of the following is NOT accelerating?
a) A car that zooms from 30 to 65 mph.
b) A biker that hits the brakes suddenly to come to a stop.
c) A person sitting on a merry-go-round that is moving at a constant speed.
d) These are all accelerating.
e) None are accelerating.
D
How fast did they go from A to B?
0.6 m/s
Instantaneous speed
Your paper airplane flies at an average speed of 5.2 m/s. How far would your paper airplane go if it stayed in the air for 100 seconds?
520 meters
Calculate the acceleration of a train that slows from 200 m/s to 50 m/s over 10 seconds.
50 - 200 / 10
-150 / 10
-15 m/s2
How far did they travel from A to E?
12 km