Contrast distance and displacement,
Distance is how fan an object moved it total.
Displacement is how far an object moved from its starting point.
Which line shows an object traveling at a constant speed?

Line C
What is the speed of a sprinter who can run 100 m in 10 s?
S = 10 m/s
What are the three types of acceleration?
1.(+) acceleration
2.(-) acceleration
3.(0) acceleration
c. Asia
Currently, Asia is Earth's largest continent at approximately 17,300,000 square miles (44,806,812 sq km). Africa comes in 2nd at 11,700,000 square miles (30,300,000 sq km).
Contrast speed and velocity.
Speed is the distance an object travels in a certain unit of time.
Velocity is speed, but with directionality.
Which line shows an object moving away, stopping, then coming back?
Line D
Which has a greater speed: a
heron that flies 600 m in 1 minute
or a duck that travels 60 m in 5 seconds?
The duck, at 12 m/s has a greater speed than the heron, which has a speed of 10 m/s.
A car slows down from 50.0 m/s to 20.0 m/s in 6.0 s. What is the acceleration?
a = (Vf – Vi) / T
a = (20.0 – 50.0) / 6.0
a = (-30.0) / 6.0
a = - 5.0 m/s2
What razor-thin country accounts for more than half of the coastline of western South America?
a.Ecuador
b.Peru
c.Brazil
d.Chile
d. Chile
With a ragged coastline of 2,650 miles (4,265 km), Chile accounts for more than half of the western coastline of South America.
Contrast instantaneous speed and average speed.
Instantaneous speed is an object’s speed at an exact moment in time.
Average speed is an object’s speed over an entire distance.
Which line(s) show 0 displacement?
Lines B and D
If the average speed of a car is 45 km/h, how far can it travel in 40 min, in meters?
Convert: 40 min à 2400 s
Convert: 45 km/h à 12.5 m/s
D = S x T
D = 12.5 m/s x 2400 s
D = 30,000 m
A speed skater finished a race. After she crossed the finish line, she coasted to a stop (0.0 m/s) on the ice. If her initial speed was 13.0 m/s and her acceleration was -2.9 m/s2, how long did it take her to stop?
a = (Vf – Vi) / T
T = (Vf – Vi) / a (rearranged)
T = (0.0 – 13.0) / -2.9
a = -13.0 / -2.9
a = 4.5 s
b. Africa
Africa is the only continent that is in all four hemispheres: north, south, west, and east.
Two objects traveling at the same speed can have different velocities if they . . .
move in different directions
What lines show acceleration? Positive? Negative?
Acceleration: Lines A, B
(+) acceleration: Line A
(-) acceleration: Line B
How fast was a plane flying if it traveled 400.0 km in 30.0 min, in km/h?
Convert: 30.0 min à 0.5 h
S = D/T
= 400.0 km / 0.5 h
= 800.0 km/h
The elevators in the Landmark Tower in Yokohama, Japan, are the fastest in the world. They accelerate from rest at 3.125 m/s2 for 4.00 s to reach their top speed. What is this final speed?
a = (Vf – Vi) / T
(Vf – Vi) = a x T (rearranged)
(Vf – 0) = 3.125 x 4.00
Vf = 12.50 m/s (~ 30 mph)
What ancient river runs through Baghdad, site of ancient Babylon?
a.Karun
b.Tigris
c.Jordan
d.Euphrates
b. Tigris
The Tigris river runs through Baghdad. It is about 1,150 miles (1,800 km) long. The name "Tigris" comes from Old Persian and translates as "the fast one".
Define: vector.
A vector is a quantity
having both magnitude
and direction.
Describe the speed of the ball at 2s. Explain what is happening.
At 2s, the ball it has 0 speed.
This is because after been thrown, the ball has reached the top of its arc and is motionless for a split second.
Sound waves travels at 330.0 m/s. How long does it take for the sound of thunder to travel 1.5 km?
Convert: 1.5 km à 1500.0 m
T = D / S
T = 1500.0 / 330.0
T = 4.5 s
A type of rocket sled used by NASA was used to measure the effects of extreme (-) acceleration. The sled reaches a top speed of 300.0 km/h, then comes to a complete stop (0.0 m/s) in 0.18 s. What is the acceleration?
Convert: 300.0 km/h à 83.3 m/s
a = (0.0 – 83.3) / 0.18
a = - 83.3 / 0.18
a = - 462.8 m/s2
What is the smallest independent country on Earth?
a.Vatican
b.Grenada
c.Monaco
d.Maldives
a.Vatican
With an area of just a half a kilometer, the Vatican is the world's smallest country. So small, it fits within the Italian capital city of Rome, and is the center of Catholicism.