This is a force that must touch one thing to exert a force on the other.
What is contact force?
100
The result of adding up all forces acting on an object, we have a ________________ force.
What is net force?
100
When the net force acting on an object is zero, we say the force is ____________________.
What is balanced?
100
The force of attraction between the masses of any two objects is called this
What is gravity?
200
A force that moves things closer
What is a pull?
200
A force that acts on something without touching it.
What is force at a distance?
200
The direction of the net force on water as it goes over a waterfall (up, down, no net force)?
What is down?
200
Unbalanced forces occur when ______________________.
What is when the forces move in one direction or another (and the net force is no longer zero)?
200
The mass of an object on earth is 120kg. The mass of this object on the moon would be ____________.
What is 120kg? (Mass, or the amount of "stuff" inside of an object never changes. Only weight changes)
300
A force between things sliding past each other called?
What is friction?
300
Objects fall to the ground instead of float in the area because of gravity, a _______________________ force.
What is Force at a Distance?
300
10 men are playing tug of war (5 men on each side). Each man is exerting a force of 100 lbs. The force exerted on the rope is ___________.
What is zero? (Explanation: The forces cancel each other out.)
(500-500= 0)
300
The forces that act on a car moving at a steady 50mph are _________________. (Balanced or Unbalanced?)
What is balanced?
300
Two forces acting on a falling object are ____________ and _________________.
What is gravity (downward arrow) and air resistance (upward arrow).
400
The force that makes a car come to a stop when the driver puts on the brakes.
What is friction?
400
When you move through the air, tiny bits of air push against you. This is a ___________________ force.
What is a contact force?
400
The weight of a person on the moon who is normally 180lbs on earth would be _______________lbs.
What is 30 lbs.
400
Name TWO forces acting on a car moving 100mph.
1) What is gravity? (holding the car down)
2) What is air resistance? (working against the car)
3) What is friction? (between the car and the road)
400
The difference between MASS and WEIGHT
What is MASS is the amount of stuff in an object. WEIGHT is the amount of force exerted by gravity.
500
Arrows show us the _____________ of a force and the _______________ the force is moving towards.
What is amount and direction?
500
Electrostatic and magnetic forces are both ___________________ forces.
What are "forces at a distance"?
500
A large object on the top of a windy hill has all FOUR different forces acting on it. However it is NOT moving! The net force on this rock is _________.
What is zero?
500
Unbalanced forces can cause an increase of speed known as ________________ a decrease in speed, known as __________________, or a change of direction.
What is acceleration and deceleration?
500
When do two poles of a magnet or two charges of electricity attract to each other?
What is when UNlike poles or charges attract. (Think Hollywood couples!)