Forces
When an object speeds up, slows down, or changes direction are the forces balanced or unbalanced?
Unbalanced
Who was the scientist that discovered that forces occur in pairs and can be either balanced or unbalanced?
Isaac Newton
True or False: Magnetic Force is a force that pulls metals towards an object without touching them
True
What is an inclined plane?
a sloped surface or ramp
***********************A First Class Lever has the.... A Second Class Lever has the.... A Third Class Lever has the....*****************************
"__________in the middle"
Fulcrum in the middle
Load in the middle
Effort in the middle
When an object is not moving at all, are the forces balanced or unbalanced?
Balanced
What non-contact force causes a basketball to bounce on the ground after Mr. T throws it?
Gravity
Is magnetic force a contact or non-contact force?
Non-contact
What is a Lever?
a rigid rod that rotates at a point or fulcrum
This type of pulley is attached to something that does not move
Fixed Pulley
When an object travels at a constant speed, are the forces balanced or unbalanced?
Balanced
True or False? The larger the object's mass, the greater the force of gravity towards it.
True
Does it take more force to start moving a merry-go round or to keep it moving?
Start it
What is a Pulley System?
one or more grooved wheels with a rope running through the groove
What is the best simple machine to use if you are trying to break apart a wooden stump?
Wedge
********************************************This type of force causes an object to change direction by touching it.***************
Contact Force
What is the mathematical relationship between the force of gravity on an object (Newtons) and its weight (grams)?
About 100 grams equals 1 Newton
True or False: Friction is a non-contact force that resists the motion of an object
False
What is a Wheel and Axle?
a large wheel connected to a small wheel through its center
This type of pulley has the rope attached to something that does not move, and the pulley attached to the load
Movable Pulley
This type of force causes an object to change direction without touching it.
Non-contact Force
Explain how gravity works when an apple falls from a tree.
Apples are pulled towards the earth because the earth is bigger
What are 3 things magnets are made of?
Iron, Nickel, Cobalt
What is a Wedge?
an incline plane that moves
What is the best simple machine to use if you have a very heavy weight you need to lift off of the ground?
Lever