Definitions
What is acceleration?
the rate at which velocity changes
a ball is moving 15 m/s east and after 5 seconds, is moving 45 m/s east.
6 m/s^2
a car slows down for a red light
negative acceleration
What 3 things does acceleration depend on?
speed direction time
what is average acceleration?
the difference in velocity divided by time elapsed
car is traveling 45 mph south to get to the store. After 15 seconds, he picks up speed and is traveling 75 mph
2 miles per hour^2
a runner goes from 6 mph to 10 mph in 10 minutes
positive acceleration
true or false: when acceleration and velocity are in opposite directions the speed will increase
false
what is positive acceleration?
an increases in velocity
dog is running 21 ft/min east. After 3 minutes, the dog speeds up to 45 ft/min
8 ft/min^2
a Ferris wheel
centripetal acceleration
what happens to speed if acceleration and velocity are in the same direction?
speed will increase
what is negative acceleration?
a decrease in velocity
the cat ran 10 m/s and after 10 seconds sped up to 60 m/s
5 m/s^2
Marie walked 10 miles in 4 hours
unknown
what is the formula for average acceleration
average acceleration= difference in velocities/time elapsed
what is centripetal acceleration?
acceleration in a circular motion
a runner has an average acceleration of 25 m/s^2. If her initial velocity was 10 m/s south and her total time was 2 seconds, what was her final velocity?
60 m/s south
a girl twirls a ribbon above her head
centripetal acceleration
What is the difference between speed and velocity?
velocity includes direction