lecture 15

# lecture 15 - Lecture 15 Collisions(1D 2D Elastic Inelastic...

This preview shows pages 1–7. Sign up to view the full content.

1 Lecture 15 Collisions (1D, 2D; Elastic, Inelastic)

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

View Full Document
2 When there are no external forces present the momentum of a system will remain unchanged. ( p i = p f ) If the kinetic energy before and after an interaction is the same, the “collision” is said to be elastic . If the kinetic energy changes, the collision is inelastic .
3 If, after a collision, the bodies remain stuck together, the loss of kinetic energy is a maximum. This type of collision is called completely inelastic .

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

View Full Document
4 Example: In a railroad freight yard an empty freight car of mass m rolls along a straight level track at 1.00 m/s and collides with an initially stationary, fully loaded, boxcar of mass 4.00 m . The two cars couple together upon collision. (a) What is the speed of the two cars after the collision? ( 29 m/s 20 . 0 0 1 2 1 1 2 1 2 1 1 1 2 1 2 1 = + = + = + = + + = + = v m m m v v m m v m v m v m p p p p p p f f i i f i
5 (b) Suppose instead that both cars are at rest after the collision with what speed was the loaded boxcar moving before the collision if the empty one had v 1i = 1.00 m/s. m/s 25 . 0 0 0 1 2 1 2 2 2 1 1 2 1 2 1 - = - = + = + + = + = i i i i f f i i f i v m m v v m v m p p p p p p Example continued

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

View Full Document
Example: Body 1 of mass M has an original velocity of 6.00 m/s in the +x-direction toward a stationary body 2 of the same mass. After the collision, body 1 has v x =+1.00 m/s and v y =+2.00 m/s. What is the magnitude of body 2’s velocity after the collision? 1
This is the end of the preview. Sign up to access the rest of the document.

{[ snackBarMessage ]}

### Page1 / 23

lecture 15 - Lecture 15 Collisions(1D 2D Elastic Inelastic...

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

View Full Document
Ask a homework question - tutors are online