Forces & Motion Mind Map
← Forces & MotionHow contact forces add up to a net force that changes motion, and how gravitational, electric, and magnetic fields push and pull without touching.
- forceA push or a pull.You use force to open a door.
- contact forceA push or pull between objects that are touching.Kicking a ball puts a contact force on it.
- applied forceA push or pull that a person or object puts on something.The applied force from my hands slid the box.
- frictionA force that opposes relative sliding, or attempted sliding, between surfaces; it can increase thermal energy.Friction slowed the sled on the grass.
- air resistanceFriction from air that pushes against a moving object. Also called drag.A parachute uses air resistance to slow down.
- normal forceA contact push perpendicular to a surface, exerted on an object touching that surface.The table’s normal force holds up the book.
- net forceThe total of all the forces acting on an object.If the net force is zero, the object’s motion does not change.
- balanced forcesForces that cancel out, so the object’s motion does not change.In a tie in tug-of-war, the forces are balanced forces.
- unbalanced forcesForces that do not cancel out, so the object speeds up, slows down, or turns.Unbalanced forces made the soccer ball change direction.
- force diagramA drawing with arrows that shows the size and direction of each force on an object.The force diagram had four arrows on the box.
- inertiaThe tendency of an object to keep doing what it is doing: stay still or keep moving.Inertia keeps you moving forward when the bus stops.
- gravityThe force that pulls objects with mass toward each other.Gravity pulls the apple to the ground.
- gravitational fieldThe area around an object with mass where it pulls on other masses.The moon stays in orbit because of Earth’s gravitational field.
- weightThe pull of gravity on an object’s mass. It changes from planet to planet, but mass does not.Your weight on the moon would be about one-sixth of your weight on Earth.
- orbitThe curved path of one object around another in space, maintained by gravity.The moon’s orbit around Earth takes about a month.
- reference pointA chosen place or object used to describe position, motion, or height.From the train, the trees seem to move, so choose your reference point carefully.
- fieldA region around an object where another object feels a force without being touched.A magnet’s field can move a paper clip from a distance.
- non-contact forceA push or pull that acts from a distance, like gravity or magnetism.Gravity is a non-contact force.
- electric chargeA property of matter that can be positive or negative and causes electric attraction or repulsion.Rubbing a balloon on hair moves electric charge.
- electric fieldThe area around a charged object where it can push or pull other charges.The electric field around the balloon pulled bits of paper.
- magnetic fieldThe area around a magnet where its force acts.Iron filings show the shape of a magnetic field.
- north poleThe end of a magnet that points toward Earth’s north when the magnet can swing freely.The north pole of one magnet pulls on the south end of another.
- south poleThe end of a magnet that points toward Earth’s south when the magnet can swing freely.Two south pole ends push each other away.
- attractTo pull toward.Opposite poles attract each other.
- repelTo push away.Like charges repel each other.
- electromagnetA magnet produced by electric current, often in a coil around an iron core; some magnetism can remain after the current stops.A junkyard crane uses an electromagnet to lift cars.
- generatorA machine that converts mechanical energy into electrical energy, commonly by moving magnets and coils relative to one another.The wind turns a generator inside the turbine.