Motion
What two things must you know to calculate speed?
total distance and total time
What may happen when an object receives unbalanced forces?
It may move
what force is shown if a lady is pushing her baby in a stroller?
Applied force
What is the SI unit for mass?
kilogram(kg)
what is the difference between speed and velocity
Velocity has direction. Speed is distance traveled over time
What is a force?
a push or pull
what type of force opposes motion, causing moving objects to slow down and/or stop?
Friction
What two things affect gravity?
1. mass
2.distance
why is it more helpful to know a tornado's velocity rather than its speed?
Velocity tell direction, allowing people to get out of danger and move in a safe direction
Describe three different ways you can accelerate when riding your bike
1. Slow down
2. speed up
3. change direction
what 2 forces are acting on a wagon that weighs 10kg(1 force goes up and the other is down)
What is gravity?
Force of attraction between objects
Emily can skateboard 120 meters in 8 seconds. What is her average speed?
15 m/s
what is the SI unit of force?
Newton(N)
The force of friction exerted by a surface depends on?
The smoothness of the surface
What is the law of universal gravitation
1.Larger mass=more gravity
2. Greater distance= less gravity
A kangaroo hops 60 meters to the east in 5 seconds. What is the kangaroos velocity?
12 m/s east
Clay and Taylor were helping a friend move a couch. Clay pushed the couch with 25 N east and Tyler pushed with 15 N east. Clay's little sister pushed back at 10 N west. Calculate the net force
30 N east
1.apply lubricant
2.Smooth surface
Describe two differences between weight and mass
1. weight is force of gravity on an object
2.mass never changes