PHY183-Lecture24

# PHY183-Lecture24 - Clicker Clicker Quiz A horizontal table...

This preview shows pages 1–2. Sign up to view the full content.

1 February 29, 2012 Physics for Scientists&Engineers 1 1 Physics for Scientists & Engineers 1 Spring Semester 2012 Lecture 24 Angular Acceleration and Centripetal Force Clicker Quiz A horizontal table rotates counterclockwise with constant angular velocity. The components of the linear acceleration are a t (tangential) and a c (centripetal). Select the correct statement with respect to the components of the acceleration. A. a t is zero and a c is radially outward B. a t is zero and a c is radially inward C. a t is zero and a c is zero D. a t is in the same direction as the linear velocity and a c is radially outward E. a t is in the same direction as the linear velocity and a c is radially inward February 29, 2012 Physics for Scientists&Engineers 1 2 February 29, 2012 Physics for Scientists&Engineers 1 3 Centripetal Acceleration on Earth What is the correction to gravity due to the centripetal acceleration on the surface of Earth? Answer: Correction between between 0.33 percent (at the equator) and 0 (at the poles). a c = ω 2 r = 2 R earth cos θ = (7.27 10 5 s -1 ) 2 (6.37 10 6 m) cos = (0.034 m/s 2 ) cos February 29, 2012 Physics for Scientists&Engineers 1 4 Example The period of rotation of the Earth is 24 hours. At this angular velocity, the centripetal acceleration at the surface of the Earth is small compared with the acceleration of gravity. What would the period of rotation of the Earth be if the magnitude of the centripetal acceleration at the surface of the Earth at the equator due to the rotation of the Earth we equal to the magnitude of the acceleration of gravity? Solving for angular speed Period 22 ce a r t h arRg ωω == = 2 6 9.81 m/s 0.00124098 rad/s 6.37 10 m earth g R = 5063.08 s 0.00124098 rad 1.41 s r / h T ππ = = February 29, 2012 Physics for Scientists&Engineers 1 5 Clicker Quiz When an object moves in a counterclockwise circle, the radial component of the acceleration is observed to be toward the center of the circle. If instead, the object moves in a clockwise circle the radial component of the acceleration is A) toward the circle’s center B) away from the circle’s center C) zero Centripetal Force The centripetal force is not another fundamental force of nature It should not be drawn on a free body diagram It is the inward force necessary to provide the centripetal acceleration necessary for circular motion It has to point inward toward the circle’s center Its magnitude is the product of the mass of the object and

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

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

## This note was uploaded on 04/02/2012 for the course PHY 183 taught by Professor Wolf during the Spring '08 term at Michigan State University.

### Page1 / 4

PHY183-Lecture24 - Clicker Clicker Quiz A horizontal table...

This preview shows document pages 1 - 2. Sign up to view the full document.

View Full Document
Ask a homework question - tutors are online