(8) Forces-Newton's 1st and 2nd Laws

(8) Forces-Newton's 1st and 2nd Laws - Lecture 8 Forces...

Info iconThis preview shows pages 1–7. 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 Document Right Arrow Icon

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

View Full Document Right Arrow Icon

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

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

Unformatted text preview: Lecture 8 Forces: Newton’s First and Second What is a force? What is a force? It’s a pull or a push. It has a magnitude and a direction F r F r Forces are vectors! Types of forces Types of forces 1. Contact forces:- Gravitational- Electric and Magnetic- Weak force (important in subatomic world)- Strong force (important in subatomic world)- Normal force (always perpendicular to contact surface); it’s the basic “push”- Tension (force through a string, cable, rope, etc): it’s the basic “pull”- Friction (appears when two surfaces slide or try to slide one against the other) 2. Action at distance or non-contact forces : (The fundamental forces of Nature!) Newton’s Three Laws Newton’s Three Laws 1. Any object remains at rest or in motion along a straight line with constant speed unless acted upon by a net force. 3. Forces occur in pairs: For every force (or action) there is an equal but opposite force (or reaction) on B by A on A by B F F = - r r 2. net all F F ma = = r r r Newton’s First Law Newton’s First Law Any object remains at rest or in motion along a straight line with constant speed unless acted upon by a net force DEMO: Air table This law tells you what happens in the absence of any force, for instance in outer space ACT: Snapped string ACT: Snapped string A small ball attached to the end of a string moves in horizontal circles on a frictionless table as shown below. If the string snaps, what will be the trajectory of the ball?...
View Full Document

{[ snackBarMessage ]}

Page1 / 21

(8) Forces-Newton's 1st and 2nd Laws - Lecture 8 Forces...

This preview shows document pages 1 - 7. Sign up to view the full document.

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