Simple Machines
Vocabulary
Calculator Please!
Random
Forces and Motion
100
a hammer
lever
100
stored energy
potential energy
100
In 0.56 seconds a rolling marble traveled 20.0 cm. What’s its average speed?
35.7 cm/sec
100
What is the formula to calculate speed?
distance divided by time
100
A push or pull
force
200
flagpole
pulley
200
Keeps planets in their orbit, pulls things down
gravity
200
If a car travels 300 miles in 5 hours, what is the speed of the car?
60miles/hour
60 mph
200
speed in a given direction is called
velocity
200
A
300
lightbulb
screw
300
speed up, slow down or change direction
acceleration
300
50N
300
When a student pushes a desk across the floor she can feel a force that is resisting the motion of the desk. What is the force?
a) gravity
b) friction
friction between the desk and the floor
300
A person has more kinetic energy when he is _____________
a) running down a hill
b) sleeping
c) standing still
d) sitting
running down a hill
400
doorknob
wheel and axle
400
speed in a given direction
velocity
400
If a boat traveled 400 km. in 5 hours, its average speed would have been
80km/hour
400
Does your weight change on the moon?
yes! Your mass stays the same
400
The faster something is going or the more it weighs, the more mass it has, the more __________ it has.
momentum
500
axe
wedge
500
This force slows things down and opposes motion
friction
500
If a runner ran a 50 meter-dash in 5.0 secs his average speed would have been ______
10m/sec
500
balanced or unbalanced?
balanced
500
A slide is an example of what simple machine?
inclined plane