W4.1 - January 25, 2008 Physics for...

Info iconThis preview shows pages 1–6. Sign up to view the full content.

View Full Document Right Arrow Icon

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

View Full DocumentRight Arrow Icon

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

View Full DocumentRight Arrow Icon

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

View Full DocumentRight Arrow Icon
This is the end of the preview. Sign up to access the rest of the document.

Unformatted text preview: January 25, 2008 Physics for Scientists&Engineers 1 1 Physics for Scientists & Physics for Scientists & Engineers 1 Engineers 1 Spring Semester 2008 Lecture 12 January 25, 2008 Physics for Scientists&Engineers 1 2 Force Force So far: describe motion of objects! Kinematics Now: find out what makes objects move! Dynamics Concept of a force force When objects interact with each other, they exert force(s) on each other Different types of interaction: different forces Contact forces: normal force, friction force Action-at-a-distance forces: gravity, electromagnetism January 25, 2008 Physics for Scientists&Engineers 1 3 Weight and Mass Weight and Mass Magnitude of gravitational force on an object = weight Gravitational force on an object, F g , is always proportional to its mass Near surface of Earth (altitude of 10 km or less): Weight is constant and is the product of objects mass and the Earths gravitational acceleration: F g = mg g = 9.81 m/s 2 January 25, 2008 Physics for Scientists&Engineers 1 4 Example: Object with mass m = 5.00 kg Gravitational force F g = mg = (5.00 kg)(9.81 m/s 2 ) = 49.05 kg m/s 2 Force Unit 1 kg m/s 2 = 1 N Named after British physicist Sir Isaac Newton (1642-1727), father of modern mechanics and perhaps the most influential scientist who ever lived Summary: mass, m , is measured in units of kg whereas weight (a force!), mg , is measured in units of N Weight and Mass Weight and Mass January 25, 2008 Physics for Scientists&Engineers 1 5 Example: Gravitational Force Example: Gravitational Force on Notebook Computer on Notebook Computer Hold computer Feels heavy, because gravity is pulling on it Gravitational force has direction: straight down Introduce standard Cartesian coordinate system !...
View Full Document

This note was uploaded on 04/06/2008 for the course PHY 183 taught by Professor Wolf during the Spring '08 term at Michigan State University.

Page1 / 22

W4.1 - January 25, 2008 Physics for...

This preview shows document pages 1 - 6. Sign up to view the full document.

View Full Document Right Arrow Icon
Ask a homework question - tutors are online