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How do I relate Food Calories to Energy ?. What is Energy?. There are two fundamental components of the physical world: Matter Energy Physics spends a lot of time dealing with energy and Chemistry with matter . Actually the two concepts are best understood together. What is Energy?.
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What is Energy? • There are two fundamental components of the physical world: • Matter • Energy Physics spends a lot of time dealing with energy and Chemistry with matter. Actually the two concepts are best understood together.
What is Energy? Energy is the ability to do work. • Everyday meaning of work. • Scientific meaning of work.
Work Work = Force x distance x Cos Ɵ W = F x d x Cos Ɵ where, F = force in Newton’s d = distance in meters W = work, in Newton meter Ɵ = angle between the force and displacement vectors, in degrees We are doing work when we exert a force on an object over a distance and the force causes the displacement of the object.
Work What are the units of measure for Work?
What is a Newton meter 1 N m = 1 Joule A Joule is an amount of energy just as a calorie is an amount of energy. The two are related using the following conversion: 1 calorie = 4.18 Joules (Remember 1Calorie = 1000 calories) Let’s do some example calculations.
Work Done on a Ball Let’s look at the simple task of rolling a ball.