Force and Motion Notes What causes the motion of an object to change? ________________________ - is a push or pull applied to an object by another object. Force has direction; a ______________ when more than one _____________ acts on an object they must be ____________________. Net-force - Balanced Forces - Example - Unbalanced Forces Example - What is inertia and how is it related to motion? _________________ - is the tendency of objects to resist all changes in motion. ➢ Objects’ motion do not change unless a net ______________ is _______________ on them. ➢ The amount of ____________ depends on the object’s _____________. o More mass = _________________________________________ o More inertia = ________________________________________ Example: Newton’s First Law of Motion Objects _________________________________________________________ Objects Quiz Questions 1. When are forces acting on an object balanced? 2. What effect do balanced forces have on an object’s motion? 3. How is inertia related to motion? 4. How is mass related to inertia? 5. Give two examples of inertia. 6. Why is Newton’s 1st Law called the law of inertia? What is the relationship between force, mass, and acceleration? Force and Acceleration The force applied to an object and its acceleration are _________________ ____________________________ _____ They both change in the ___________ direction 10 times more force results in 10 times more __________________ 10 times less force results in 10 times less Newton’s 2nd __________ Law of Motion Mass and Acceleration The mass of an object and its acceleration are _________________ ______________ They change in _____________ directions 10 times more mass results in 10 10 times less times less mass results in ______________________ 10 times more ______________ ________ F=mxa m = F/a a =F/m Units of force – F = kg x m/s2 = ______________ What net force is required to make a 2 kg object accelerate at 9.8 m/s2? What is the mass of an object if 6 N of net force cause the object to accelerate at 3 m/s2? If a force of 5 N net force is applied to a 0.5 kg object, what will its acceleration be? Examples of Newton’s 2nd Law: Quiz Questions What does it mean to say that force and acceleration are directly proportional? What does mean to say that mass and acceleration are inversely proportional? N = ________________________ What is the mass of a car that requires 1200 N of net force to make it accelerate at 0.5 m/s2? What net force is needed cause a 0.55 kg ball to it accelerate at 4 m/s2? If 250 N of net force is applied to a 3 kg box, what acceleration will it have? What is gravity and what affects the size of the force? Gravity – 2 factors that affect gravity – The ___________ of the 2 objects The ___________________ between the objects Gravity on Earth = __________________ F weight = ______________ x ______________ The force of Friction _________________ - is a force that opposes motion Types of Friction 1. 2. 3. 4. How are mass and weight different? Quiz Questions What is your weight in Newtons? 1 lb = 4.5 N What is your mass? G = 9.8 m/s2 (F = ma) What would you weigh on the moon? G = 1.6 m/s2 What would you weigh on the moon in pounds? 1 lb = 4.5 N What would your mass be one moon? How does Newton’s Third Law of Motion apply to everyday situations? Action = _____________________ Describes how objects __________________ with each other When one object exerts a force on another object, the second object exerts __________________________________________________________ on the first.