Car Collision Forensics Lab

Slides:



Advertisements
Similar presentations
Momentum Conservation
Advertisements

Momentum-Impulse Theorem Collision:
Car Crash Investigation Lab
Abby Pombert Kayleigh Artise Chris Lam
6.3 Elastic and Inelastic Collisions
Collisions Deriving some equations for specific situations in the most general forms.
Chapter 5 Momentum Ewen et al. 2005) Objective: Apply the law of conservation of momentum to both elastic and inelastic collisions of two objects. Apply.
Aim: How can we apply conservation of momentum to collisions? Aim: How can we apply conservation of momentum to collisions? Identify conservation laws.
Problem of the Day An 1800 kg car stopped at a traffic light is struck from the rear by a 900 kg car, and the two become entangled, moving along the same.
Chapter Elastic and inelastic collision. Objectives Identify different types of collisions. Determine the changes in kinetic energy during perfectly.
Linear Momentum why is more force needed to stop a train than a car if both travel at the same speed? why does a little tiny bullet have so much impact?
Conservation of Momentum The sum of the momentums of two bodies before they collide is equal to the sum of their momentums after they collide if there.
Warm up. Physics Honors AB –Day 1/12/15-1/13/15 Momentum and Impulse.
PHYSICS 231 INTRODUCTORY PHYSICS I Lecture 8. Work for nonconstant force Spring force Potential Energy of Spring Power Last Lecture FxFx x.
AP Physics Impulse and Momentum. Which do you think has more momentum?
Collisions and Momentum 3.1 pp Mr. Richter.
Chapter 6: Momentum and Collisions!
Chapter 7 Linear Momentum. Chapter Momentum Linear Momentum- product of mass times velocity p=mvp=momentum units=kg.m/sec Restate Newton’s second.
Chapter 6 Momentum and Collisions. Chapter Objectives Define linear momentum Compare the momentum of different objects Describe impulse Conservation of.
Momentum & Collisions Physics - Chapter 6. Momentum  Vector quantity  Product of an objects mass and velocity  Represented by p  SI units of kg x.
Chapter 6 Momentum and Impulse
Momentum and Its Conservation LEQ: What is Momentum?
Collisions.
Chapter 6 Momentum and Impulse. Momentum The product of an object’s mass and velocity: p = mv Momentum, p, and velocity, v, are vector quantities, meaning.
Chapter 2, Section 3 Momentum Notes. Momentum, Mass and Velocity.
Chapter 9 - Collisions Momentum and force Conservation of momentum
Impulse and Momentum AP Physics B.
Car Crash Abby Pombert Kayleigh Artise Chris Lam.
Preview Objectives Linear Momentum Chapter 6 Section 1 Momentum and Impulse.
Momentum Learning Intention: Understand and be able to support the claim of conservation of momentum in a system.
Inelastic Collision An elastic collision is an encounter between two bodies in which the total kinetic energy of the two bodies after the encounter is.
Chapter 6 Momentum and Collisions. 6.1 Momentum and Impulse Linear Momentum After a bowling ball strikes the pins, its speed and direction change. So.
Impulse, Momentum and Collisions. momentum = mass x velocity p = mv units: kgm/s or Ns.
Chapter 7 Linear Momentum. Objectives: Students will be able to: Explain that a conserved quantity is a quantity that remains numerically constant. Define.
Lecture 14: Collisions & Momentum. Questions of Yesterday A 50-kg object is traveling with a speed of 100 m/s and a 100-kg object is traveling at a speed.
Conservation of Momentum. For a collision occurring between two objects in an isolated system, the total momentum of the two objects before the collision.
Momentum and Collisions. Conservation of Momentum.
Chapter 6 Momentum and Collisions 6-1 Momentum and Impulse Momentum(p) describes the tendency of an object to continue moving (or not moving) at a constant.
1. What is the difference in elastic and inelastic collisions?
6-3: Elastic and Inelastic Collisions Objectives: Identify different types of collisions Determine the decrease in kinetic energy during perfectly inelastic.
Chapter 9 Momentum Is equal to the mass of an object times the velocity of an object Has the symbol “p” so p= m v - measured in kgm/s - It is a vector.
Warm up A 3.00 kg crate slides down a 7 m ramp. The height of the ramp is 5 m off the ground. The velocity of the crate at the bottom of the ramp is 5.
Momentum. Inertia in motion momentum (p) is equal to mass x velocity units for momentum: kg· m/s.
Bell Ringer After reading the article Does slamming on the brakes save your brake pads? Do you believe this saves gas?
Momentum & Impulse. Momentum The linear momentum of an object is defined as: Momentum = mass x velocity p = m x ѵ ‘p’ is used because the word "impetus"
Elastic and Inelastic Collisions
Chapter 6. When objects collide their motion changes and this is the result of a concept called momentum. Momentum = mass x velocity p = mv kgm/s or Ns.
1. A train car of mass 4.00 x 10 3 kg is moving at +6.0 m/s. It collides with a stationary car of mass 6.00 x 10 3 kg. The cars couple together. Find the.
Momentum, Impulses, and Collisions. A. Background Information 1.Momentum of an object is anything that has inertia and is moving a. It is based on an.
Chapter 6 Preview Objectives Linear Momentum
Guidelines for Solving Conservation of Momentum Problems
3.1.2 Conservation of Momentum
Collisions.
Momentum Conservation
Elastic Collisions.
Chapter 6 Objectives Identify different types of collisions.
Linear Momentum AP Physics.
Momentum Chapter 1 Section 3.
7. Momentum and impulse Momentum:
Handout, Test Correction, Copy down table
Momentum Conservation of Momentum
Chapter 7 Impulse and Momentum.
Elastic Collisions.
Acceleration and Momentum   Acceleration — Rate of change of velocity (speed and specific direction) over time. Positive Acceleration- speed increases.
The Law of Conservation of Momentum
SCI 340 L22 Collisions basically include every interaction
Chapter 6 Momentum and Collisions
Collisions.
Collisions.
Collisions Chapter 7.5.
Presentation transcript:

Car Collision Forensics Lab Ben O’Donnell, Robert Robinson, Jack O’Donnell

Introduction A traffic accident occurred in a 35 km/hr speed limit zone on Millway Street in which a 3000-kg Cadillac Escalade SUV rear-ended a 2000-kg Subaru Outback Wagon that was stopped at a stop sign. The entire police investigative division has gone on vacation to Bora Bora to relax, so the mayor has contracted with you and your team of experts to determine what happened and what traffic laws were broken.

Accident Schematic

Auto Expert In order to solve this portion of the lab we have to use a kinematics equation from an earlier chapter. Vf^(2 )=Vi^2+2a∆x We then plug in what we know from the information given to us in the problem. We know that the SUV has a mass of 3000kg, and the Wagon has a mass of 2000kg. We also know that the acceleration of the SUV with its brakes locked is -2m/s^2, and that the acceleration of the Wagon with its brakes locked is -3m/s^2. We then use this information to solve two kinematics problems, one for the final velocity of the wagon, the other for the final velocity of the SUV. Wagon: Vf^2=(0)^2+2(-3m/s^2 )(24) Vf^2= -144 Vf^2= √144 Vf=12 m/s SUV: Vf^2=(0)^2+2((-2m)/s^2 )(2) Vf^2= -8 Vf^2= √8 Vf=2.8 m/s So immediately after the collision the Subaru wagon had a velocity of 12 m/s. The SUV had a velocity of 2.8 m/s.

Collision Expert I had to find the initial velocity of the SUV using the equation I found the SUV was traveling at a speed of 10.8 meters per second when it rear ended the Wagon X= Wagon Y= SUV (𝑉_𝑖 𝑥)(𝑚𝑥)+(𝑉_𝑖 𝑦)(𝑚𝑦)=(𝑉_𝑓 𝑥)(𝑚𝑥)+(𝑉_𝑓 𝑦)(𝑚𝑦) (0)(2000)+(𝑉_𝑖 𝑦)(3000)=(12)(2000)+(2.8)(3000) 0+(𝑉_𝑖 𝑦)(3000)=24000+8400 (𝑉_𝑖 𝑦)(3000)=32400 (𝑉_𝑖 𝑦)=10.8 𝑚/𝑠

Investigator In the world of physics there are three types of collisions, these types are known as elastic, inelastic and perfectly inelastic. An Elastic Collision is when two objects collide and bounce off of each other with no deformation and have the same kinetic energy before and after the collision. An Inelastic Collision is exactly the opposite, with two objects colliding and a deformation occurring. A Perfect Inelastic collision occurs when two objects collide and move together as one object (such as throwing two pieces of clay together. This crash exhibits characteristics of an inelastic collision. This is due to the fact that the two vehicles did dot stay joined together after the collision (the two vehicles had different final velocities). Using the kinetic energy formula (KE= ½ m*v^2) you can determine that the kinetic energies for the vehicles is different in the beginning than it is in the end. Before: KEsuv= ½ (3000)x (10.8^2)= 174.96 KJ KEwag= ½ (2000)x (0^2)= 0 KJ After: KEsuv= ½ (3000)x (2.8^2)= 11.76 KJ KEwag= ½ (2000)x (12^2)= 144 KJ If added together the kinetic energies do not match (note: some energy is given off as heat) (174.96 does not = 155.76). So the only collision type left is an inelastic collision

Conclusion The cars collided with the SUV having a velocity of 10.8 m/s. The Subaru was at rest. After the accident the cars had a velocity of 12 m/s (Subaru) and 2.8 m/s (SUV). The type of collision that the cars experienced was a inelastic collision.