Newton's Laws of Motion and Forces: Understanding Inertia, Net Force, and Gravity, Slides of Advanced Physics

Download Newton's Laws of Motion and Forces: Understanding Inertia, Net Force, and Gravity and more Slides Advanced Physics in PDF only on Docsity! Physics docsity.com The plan: • Video clip of the day • Intro to forces • Forces continued • Inertia • Newton’s Laws of Motion. • Mass & weight docsity.com Forces: • What is a force? – a force is defined as a push or a pull. • Some forces occur when one object touches another. Some objects are pulled by a force called gravity. Some forces, like that of gravity, cause an object to accelerate. docsity.com Forces: • Forces are vectors thus they will need a direction to indicate how the force is acting on an object. • Example: – Buoyant Force (+) – Gravitational Force (-) docsity.com Natural forces: • 1) Gravitational force: an attractive force that exists between all objects. It is the weakest force. • 2) Electromagnetic force: these forces result from electric charge. Charged particles at rest or in motion exert electric charges on one another and particles in motion produce magnetic forces on each other. It is very large compared to the gravitational force. docsity.com Newton’s Laws of Motion: • Newton's First Law: Inertia – An object with no net force acting on it remains at rest or with a constant velocity. docsity.com Newton’s Laws of Motion: • Newton's First Law: Inertia – an object with no force acting on it moves with constant velocity. – “Things at rest stay at rest and things in motion stay in motion” docsity.com Demonstration 2: • Rolling a ball across the floor. • What’s the force that is keeping the ball rolling? docsity.com • Inertia - tendency for an object not to change its motion. docsity.com Textbook Transfer Demonstration: docsity.com • Inertia is the tendency for an object not to change its motion. docsity.com Inertia Demonstrations: • Newspaper vs. piece of wood docsity.com Inertia Demonstrations: • Pennies & thin blade docsity.com Inertia Demonstrations: • String & weight demonstration docsity.com Balanced Forces: • A marble is accelerated by an force in the rightward direction. The marble rolls along a frictionless level surface. – What will happen to the objects velocity? – What role does acceleration play? docsity.com Unbalanced Forces: • A marble is accelerated by an force in the rightward direction. The marble rolls down an inclined plane. – What will happen to the objects velocity? – What role does acceleration play? docsity.com Unbalanced Force: • A marble is accelerated by an force in the rightward direction. The marble begins to roll up the inclined plane. – What will happen to the marbles velocity? – What role does acceleration play? docsity.com Newton’s Second Law: • “to move an object with mass you need a force.” • the acceleration of an object is directly proportional to the net force on it and inversely proportional to its mass. • Force = (mass)(acceleration) • F = m a docsity.com International Units (SI) Quantity Symbol SI Unit Force Mass Acceleration F m a N (Newtons) Kg (Kilograms) m/s2 (metres per second squared) docsity.com • F = m a docsity.com Common misconception: •WEIGHT DOES NOT EQUAL MASS! docsity.com Weight: • An objects weight is Fg is the product of its mass m, and the acceleration due to gravity, g. • Fg = mg • Fg = force of gravity in newtons (N) • m = mass in kilograms (kg) • g = acceleration due to gravity (m/s2) docsity.com docsity.com Force Diagram: • How to start diagrams with forces in place. docsity.com Example Questions: 1) What net force is required to accelerate a 1500.00 kg race car at 3.00 m/s2 on a frictionless surface? docsity.com docsity.com