1. Define forcea push or pull that acts on an object. What is the difference between a balanced force and unbalanced force? When the forces on an object are balanced, the net force is zero and there is no change in the object’s motion When an unbalanced force acts on an object, the object accelerates or moves. What is the net force?The net force is the overall force acting on an object after all the forces are combined. How do you combine forces?Forces in the same direction add together and forces in opposite direction subtract from one another

2. Define frictionFriction is a force that opposes the motion of objects that touch as they move past each other. What are the four main types of friction?Static Sliding Rolling and Fluid Describe static friction.is the force that acts on objects that are not moving. It always acts in the opposite direction opposite of the applied force. Describe sliding frictionis a force that opposes the movement of an object as it slides over a surface. It’s less than static friction and less force is needed to keep an object moving than to start it moving.

3. What does rolling friction act on?acts on rolling objects. It acts to replace sliding friction. What does Fluid Friction act on?opposes the motion of an object through a fluid [air, water, etc…]. What is air resistance?Fluid friction acting on an object moving through the air is known as air resistance What is Newton’s first law?An object at rest remains at rest and an object in motion maintains its velocity unless it experiences an unbalanced force

4. What is inertia?Inertia is the tendency of an object to resist a change in its motion. What is Newton’s second law?acceleration of an object is equal to the net force acting on it divided by the objects mass. What is the equation for force? What is the unit for force? Force = mass x acceleration N= newton A newton is equal to what units? 1Kg x 1 Meter/ 1 second ^2

5. What is Newton’s third law?Whenever one object exerts a force on a second object, the second object exerts an equal and opposite force on the first object. Define MomentumMomentum is a property of all moving objects which is equal to the product of the mass and the velocity of the object. The bigger the momentum, the harder an object is to stop. What is the unit for momentum? The SI unit of momentum is kg ∙ m/s What is the equation for momentum?Momentum= mass x velocity

6. Define weightWeight is the gravitational force an object experiences because of its mass What is weight’s unit?Since weight is a force, the SI unit of weight is the Newton. What does the law of universal gravitation state? The law of universal gravitation states that all objects in the universe attract each other through gravitational force. What increases and decreases the gravitational force? Gravitational force increases as mass (m) increases. Gravitational force decreases as distance (d) increases.

7. Define terminal velocity Define free fall Why do satellites orbit the Earth?