Force and Motion Energy

Force A force is a push or pull that acts on an object A force can- Make an object start moving Make an object speed up, slow down, or stop Change the direction in which an object moves

Force A force is needed to make an object move. When you apply more force to an object, the object’s motion changes more. You need to use more force to move objects with more mass. Mass is the amount of material in an object.

Friction Friction is a force that happens between objects that are touching and acts against, or opposes, their motion Rough surfaces will create more friction. Smooth surfaces will create less friction. Friction can stop an object from moving or slow it down.

Gravity Gravity is the force that acts between objects that have mass, causing them to pull toward, or attract, each other. Gravity is stronger between objects that have more mass. Gravity is also stronger between objects that are closer together.

Weight Weight is the measurement of the force of gravity on an object. Weight and mass are not the same. Weight is the act of gravity on an object Mass is the amount of matter in an object

Motion Location is the position of an object. Motion happens when an object changes position because of a force. Distance is how far it is from one point to another. Measure in feet, yards, miles, cm, m, and km.

Speed Speed is a measure of how quickly an objects position changes. To find an object’s speed- Identify the distance an object moves Identify the amount of time it took to move that distance Speed = distance / time 20 yards / 2 hours = 10 yards per hour

Velocity and Acceleration Velocity is the measure of both speed and direction. It lets you figure out the position of moving objects at any time. Acceleration is any change in an object’s velocity. It takes more force to accelerate objects with more mass. They are both closely related.

Energy Energy is the ability to make changes occur. 2 types of Energy Potential Energy is energy at rest. Kinetic Energy is energy that is moving.

Magnetic Forces Magnets can pull on, or attract, certain objects. The force of a magnet is called magnetic force. A magnetic field is the area of magnetic force around the magnetic. Opposites or unlike poles attract each other Like poles push away or repel each other

Newton’s Laws of Motion Sir Isaac Newton was an English scientist that wrote 3 laws of motion. He studied how things in nature move. He explained that the motion of objects follow 3 basic laws. The laws of motion predict what happens when forces act on objects.

Newton’s 1st Law of Motion An object at rest will not move until a net force acts on it. An object that is moving will keep moving at the same speed and in the same direction until a net force acts on it. Inertia is a property that describes how objects keep moving or still until a net force acts on them.

Newton’s 2nd Law of Motion An object’s acceleration depends on the amount of force acting on the object and on the object’s mass. An object acted on by a net force will accelerate in the direction of the net force. This law describes how acceleration, force, and mass relate to each other.

Newton’s 3rd Law of Motion For every action force acting on an object, the object will apply an equal and opposite reaction force. This law describes how forces come in pairs.