Definitions
Define motion
A change in position
Which has the greatest speed? Someone running 3 mph or someone running 5 mph
5 mph
Stay at rest
What is a force?
A push or pull on an object
Can an object in motion be still?
Define position
Where something is
Which has the greater speed? A marble rolling 10 m/s or a marble rolling 11 m/s
11 m/s
Anything heavier than a pencil
What is gravity?
A force that pulls things together
I kick a soccer ball into a group of other soccer balls. What will most likely happen to them?
They will collide and change direction as they move
Define speed
Distance traveled over time
Lenny and Penny run a 500 m race. Lenny finished in 2 minutes, Penny finished in 30 seconds. Who had the greatest speed?
Penny
What can cause objects in motion to slow down or stop their motion?
Friction
If I roll a marble down a wooden ramp and down a carpeted ramp, which marble would experience more friction?
The carpeted ramp
If a ball is moving at 10 meters per second, how far will it travel in 5 seconds?
50 meters
Define friction
A force that slows or stops the motion of objects as they rub together
Marble A travels 5 meters on a table in 3 seconds. Marble B travels 2 meters on the carpet in 3 seconds. Which had the greater speed?
Marble A
Newton's 3rd Law says that every action has an equal and opposite reaction. As I'm swimming I'm pushing water backwards. What is the equal and opposite reaction?
Me moving forward while swimming
I roll marbles down a glass ramp, a wooden ramp, and a carpet ramp. Which would experience the least amount of friction?
The glass ramp
What are 2 tools I need to measure speed?
A meter/yard stick (or something to measure distance) and a timer
Define acceleration
Speeding up, slowing down, or changing direction
Boat A travels 100 meters in 10 minutes. What is their speed in meters per minute?
Boat B travels 5 meters per minute. Are they faster or slower than Boat A?
10 meters/min, and B is slower than A.
An adult elephant has a mass of about 5,000kg. A great white shark has a mass of about 2,500kg. Which would take more force to accelerate?
The elephant
How does an air hockey work, and how does it eliminate friction?
It pushes air up and makes the hockey puck hover on the table. There is less friction because the puck glides over the table.
A park is building a new slide and want it to be as smooth as possible so kids can slide super fast. Give me an idea on how they could reduce friction
They could make it a water slide, they could make it smooth plastic, they could make it smooth metal, etc.