# Ch9 HW1 - WebAssign Ch9 HW1(Homework Current Score 26.5 out...

This preview shows pages 1–3. Sign up to view the full content.

Ch9 HW1 (Homework) Arthur Barfield PHYS 2211, section M, Fall 2008 Instructor: Jennifer Curtis Web Assign Current Score: 26.5 out of 26.5 Due: Wednesday, October 29, 2008 09:00 AM EDT Description Energy and momentum in collisions Instructions Reading: Section 9.1-9.3 In this assignment you may submit each question part (answer box) separately. Different numbers of submissions are allowed for each part -- Click Show Details to see this. The due date for this assignment is past. Your work can be viewed below, but no changes can be made. 1. [MI2 09.X.00] 4/4 points A ball whose mass is 0.2 kg hits the floor with a speed of 5 m/s and rebounds upward with a speed of 2 m/s. If the ball was in contact with the floor for 2 ms ( 2 10 -3 s), what was the average magnitude of the force exerted on the ball by the floor? F avg = 700 700 N. Calculate the magnitude of the gravitational force that the Earth exerts on the ball: mg = 1.96 1.96 N In a collision, for a brief time there are forces between the colliding objects that are much greater than external forces. Which of the following is true during the collision between the bouncing ball and the floor? The magnitude of the gravitational force exerted by the Earth is much greater than the magnitude of the force exerted by the floor. The magnitude of the force exerted by the floor is much greater than the magnitude of the gravitational force exerted by the Earth. The force exerted by the floor and the gravitational force exerted by the Earth are approximately equal in magnitude.

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

View Full Document
Solution or Explanation p y = F y t p y,f - p y,i = -mg t Pay careful attention to the sign of the y component of the momentum. The initial p y is negative, while the final p y is positive.
This is the end of the preview. Sign up to access the rest of the document.

## This note was uploaded on 04/19/2010 for the course PHYS 2212 taught by Professor Kindermann during the Spring '09 term at Georgia Tech.

### Page1 / 5

Ch9 HW1 - WebAssign Ch9 HW1(Homework Current Score 26.5 out...

This preview shows document pages 1 - 3. Sign up to view the full document.

View Full Document
Ask a homework question - tutors are online