Force and Motion

Motion Motion is an object changing its position over time. How far an object moved in a certain amount of time. Often shown in Miles Per Hour (MPH) or meters per second (mps).

Force A push or a pull Force can be applied to an object to change it’s motion. Force can make an object in motion change it’s direction

Balanced Force Balanced forces cause an object to stay in place. A table can represent a balanced force: Gravity is pulling it down while the floor is pushing up on it with equal force. The table remains still.

Unbalanced Force Unbalanced forces cause objects to start moving, stop moving, or change direction. Unbalanced forces change the motion of objects. 3 factors: direction of force applied, strength of the force, mass of the object.

Direction The direction that a force is applied will determine the direction of the motion of the object.

Gravitational Force “Gravity” The attraction one object has for other objects. All objects exert a gravitational force on all other objects. The more matter an object has, the more gravity it will have.

Gravity

Friction A force that acts in the opposite direction of an objects motion. When objects touch their surfaces interact. Moving one surface across another creates friction. If you rub the surface of your hands together quickly you will feel heat, heat is created by friction.

Air Resistance Friction between a moving object and the air it is passing through. If you hold your hand out of a car window while traveling you will feel air resistance. Air resistance keeps race cars from going any faster.

Axis The point that an object rotates around

Position Where an object is at during a certain time.

Speed The distance an object moves in a certain amount of time.

Energy Energy is needed to make force happen. Energy is the ability to do work.

Work Applying force to an object to move it.

Inertia An object at rest wants to stay at rest. Inertia EggInertia Egg Video

Acceleration A measurement of how speed changes Acceleration

Velocity Speed with direction.

Momentum The measure of the amount of force that it would take to stop a moving object. Due to its mass and speed.

Drag Friction with a gas or liquid. Air Resistance.

Properties Things that describe an object.

Qualitative Description Properties of matter described using words. Example: The soft chair is blue with stripes and it smells like flowers.

Quantitative Description Properties of matter described using numbers. Example: The chair has two wheels and four legs. Example: The toy car has a mass of 50 grams.

Conservation of Energy Energy cannot be created or destroyed, but can change form or be transferred from one thing to another.

Kinetic Energy The energy that a moving object has.

Potential Energy Stored Energy.

6 Types of Simple Machines Inclined Plane Lever Wheel and Axle Wedge Pulley Screw

Simple Machines Change the amount of force needed to move an object. Make it easier for us to do work.

Inclined Plane Also called ramps, they help us move an object from a low place to a high place.

Lever Is used to move heavy objects. A fulcrum is placed in the middle to create leverage.

Wheel and Axle Where a round object (wheel) rotates around a rod (axle) to help it move smoothly.

Wedge Two inclined planes stuck together, it is used to push things apart.

Pulley A wheel with a groove around the middle, a rope fits into the groove and wraps around the wheel. Force needed to lift a weight is about half when using a pulley.

Screw An inclined plane wrapped around a center shaft, called threads. It is used by turning to pull things together.

Gear A wheel with teeth around the outside to connect with other gears. They can change the amount of force needed to move an object.

Newton The metric measurement of force. 1 N = 1kg x 1m / (s x s) One Newton is equal to the force needed to move one kilogram one meter in one second.

Mechanical Advantage How much a machine helps increase force.