Speed & Velocity
Define speed?
Distance divided by time
What does a straight diagonal line on a distance-time graph represent?
constant speed
Define acceleration (formula)
Vf- Vi/ t
What is interia?
Resistance to change in motion
Ben Zobrist runs towards home plate at a speed of 8.5 mph. What is this an example of?
velocity
A car travels 150 meters in 10 seconds. What is its speed?
15m/s^2
What does a horizontal line represent?
object is stopped (no motion)
A car speeds up from 10 m/s to 20 m/s in 5 seconds. What is her acceleration?
2m/s^2
Which has more momentum: a 2 kg ball at 10 m/x or 5 kg ball at 10 m/s?
5 kg ball
A gymnast does a flip on the balance beam. What is this an example of?
acceleration
What is the difference between speed and velocity?
Velocity includes direction
If the line becomes steeper, what does that mean?
greater speed
Can you have acceleration if speed stays the same?
Yes, if direction changes
What two factors affect momentum?
mass & velocity
A cheetah runs 93 km/h across the Savannahs. What is this an example of?
speed
A runner goes 200 m East in 25s. What is the velocity?
8 m/s East
If a graph slopes downward, what is happening?
negative acceleration
A skateboard slows from 12 m/s to 6 m/s in 3 seconds. What is the skateboarder's acceleration?
-2 m/s^2
Why do passengers move forward when a car suddenly stops?
Inertia
A runner travels 500 m in 100 s.
5 m/s
A plane travels 400 km West in 4 hours. What is its velocity
100 km/h west
A speed at a given instant can be read off of a speedometer. What is it called?
A car changes from 0 m/s to 30 m/s in 5 seconds. What is its acceleration?
6 m/s^2
An object at rest has this momentum?
zero
The change in position of an object is called this.
displacement