Lecture_10

# Lecture_10 - Pterodactyls watch as an asteroid plunges thru...

This preview shows pages 1–5. Sign up to view the full content.

This preview has intentionally blurred sections. Sign up to view the full version.

View Full Document
Pterodactyls watch as an asteroid plunges thru Earth’s atmosphere. This is an artist’s conception of a catastrophic event thought to have led to the extinction of the dinosaurs. During an impact, an asteroid only 1 km across releases its energy of motion as heat and light, delivering the explosive equivalent of 100 million atomic bombs.
Chapter 6 – Work and Energy 6.1 Work done by a constant force Energy. What is it??? You all probably have an idea of what energy is. It comes in many forms: mechanical, chemical, heat, light, nuclear, etc. And energy comes in two types: Kinetic Energy – Energy of motion Potential Energy – Energy due to position Energy is governed by certain laws which we will learn in this chapter. And we will find that solving certain problems with an energy approach is often much easier than using Newton’s Laws. But both of these very different approaches are linked through a common concept, and that is the concept of Work . We all have our own ideas about what work means to us, but in physics, work is very explicitly defined. It is defined in terms of Force and Displacement . Work done on an object by a constant force : d F d = W (*Note: Do not confuse work with weight!)

This preview has intentionally blurred sections. Sign up to view the full version.

View Full Document
d F d = W In words, Work is equal to Force times distance. In the equation for work, F d is not necessarily the total force on the object, but it is the net force (or component of the force) along the direction of motion, i.e. either in the same direction as the displacement, d , or in the opposite direction of the displacement, d . Work is a scalar , not a vector, but it can be either positive or negative. Work is
This is the end of the preview. Sign up to access the rest of the document.

{[ snackBarMessage ]}

### Page1 / 12

Lecture_10 - Pterodactyls watch as an asteroid plunges thru...

This preview shows document pages 1 - 5. Sign up to view the full document.

View Full Document
Ask a homework question - tutors are online