A-2

James, Nami, Jerry



__Location__: intersection of Piermont Ave. and Kinderkamack Rd. in Hillsdale; the intersection is level, and controlled by a stoplight. The road surface is made from asphalt, appears dry with races of sand and/or dirt __Weather__: 58 degrees Fahrenheit, sunny with few clouds __Speed Limits__: Kinderkamack Road =
 * Exhibit 1:** Scenario

=Vehicles= Color: Grey Contact Damage: Occurred on** **front right corner and entire right quarter panel** Color: Red **
 * MV1: 1999 Toyota Camry-LE**
 * Mass of Vehicle: 1375 kg
 * MV2: 2005 Honda Civic-Hybrid

=Pictures= 1. Where the two cars crashed

2. Piermont Ave. (oncoming)

3. Kinderkamack Road (oncoming)

MV1: 1999 Toyota Camry
 * Exhibit 2**: Vehicle information
 * Specs = [|1999 Toyota Camry Specs]
 * Mass = 1375kg
 * Speed = 25mpg (driver testimony)
 * Came to rest parallel to and entangled with the driver side of MV2
 * Front right corner zone of entire right qurater panel = heavey contact damage
 * Tires have normal wear
 * Right front tire was flat
 * Aluminum hub was cracked

MV2: 2005 Honda Civic-Hybrid
 * Specs = [|2005 Honda Civic-Hybrid Specs]
 * Mass = 1217kg
 * Speed = 38.3mph (from EDR)
 * Driver side came to rest parallel and entangled with passenger side of MV1
 * Driver's door is crushed inward
 * Crush zone = 3-4 feet wide, maximum depth of 2 feet
 * Steering wheel and driver's seat are displaced towards the passenger side of the vehicle
 * Driver = deceased at the scene
 * Left front tire twisted towards the right
 * Tires appear to have normal wear
 * Grey paint (from MV1) was found along the full length of the driver's side


 * Exhibit 3**: Skid Marks and Distances
 * Skid mark 1 of MV1 (left) = 50ft = 15.24m
 * Skid mark 1 of MV1 (right) = 52.5ft = 16m
 * Skid mark 2 of MV1 (left) = 5ft = 1.524m
 * Skid mark 2 of MV1 (right) = 3.75ft = 1.143m
 * Total skid mark of MV1 (left) = 16.764m
 * Total skid mark of MV1 (right) = 17.143m
 * Average skid mark of MV1 = 16.9535m
 * Distance from collision to rest of MV1 and MV2 = 40ft = 12.192m


 * Exhibit 4**: Angle Measurements
 * Angle of approaching MV1 = 6.2degrees
 * Angle of approaching MV2 = 90degrees
 * Angle of post collision of MV1 and MV2 = 54degrees

MV1 MV2 Sample Calculation (Using Trial 1 of MV1) Total crush energy = 110800Nm
 * Exhibit 5:** Damage and Crush Energy

Data Table of Coefficient of Friction Graph: Coefficient of Friction Drag coefficient = 0.738
 * Exhibit 6**: Drag Coefficient

Using momentum and glancing collisions x component: (v)(1465)(cos6.2°) + (17.12)(1217)(cos90°) = (v’)(2675)(cos54°) y component: (v)(1465)(sin6.2°) + (17.12)(1217)(cos90°) = (v’)(2675)(sin54°)
 * Exhibit 7**: Post collision speed of MV1 and MV2

1456.4v = 1572.3v' v = 1.08v'

158.2v + 20835.04 = 2164v' 170.86v' + 20835.04 = 2164v' v' = 10.45m/s


 * Exhibit 8**: Speed of MV1 at the crash (when MV1 was braking):

Using CE Using EdHeads equation d = distance (ft) (used the skid distance) f = drag factor n = percentage of braking (We inferred that it was between 100% and 40% breaking because the skid marks show a significant amount of breaking, but there was not as much damage on MV2, nor was MV2 pushed sideways, so there may not have been that much braking. Also, we read that if the two front tires skid, it is 100% braking, and if the 2 back tires skid, then it is 40% braking. We took the average.)
 * Used the CE of MV2 because MV1 made the crush in MV2 which shows its energy

**
 * Exhibit 9: Vi of MV1 before breaking using Newton's Second Law and Kinematics


 * Date || Accomplishments ||
 * 4/19 || Completed and uploaded group contract. Reviewed scenario and started discussing it. ||
 * 4/20 || Learned about real life applications of dynamics, projectile motion, and conservation of energy and momentum. ||
 * 4/21 || Began breaking down our scenario, relating concepts from EdHeads Activity that can be applied to our task. Started discussing important topics to research. ||
 * 4/22 || Took notes on glancing collisions. ||
 * 4/23 || Performed glancing collision lab using hover discs. Recorded data in lab journals. ||
 * 4/26 || Calculated maximum and minimum post collision speed using concepts from the EdHeads Activity (drag coefficient) and concepts learned in class (free body diagram, friction, net forces) ||
 * 4/27 || Learned about crush energy (how to solve for and its relationship to KE and PE), performed crush lab, performed reaction time lab, recorded data and discussed the correlation between our data and the collision scenario. ||
 * 4/28 || Solved for velocity of ball dropped in crush lab using two methods, v from CE and v from PEg. Calculated percent error and compared to data collected by classmates. Solved for the CE of the two cars in our scenario to determine the final velocities of each car before the collision. ||
 * 4/29 || Compared calculations for each car's velocity and began keynote presentation. ||
 * 4/30 || Completed EdHeads assessment. Performed Drag Coefficient Lab and collected data. ||
 * 5/3 || Uploaded background info (pictures of intersection, vehicles) and performed calculations for approach speed. ||
 * 5/4 || Organized exhibits and finished keynote presentation. Prepared for oral presentation. ||
 * 5/5 ||  ||

= =

=Measuring Crush Energy Lab=

__**Objective**__: Estimate the crush energy from damage measurements on an aluminum soda can. The can will serve as an approximate model of an automobile


 * __Hypothesis__**: The crush energy will be the same as the initial kinetic energy and the initial potential energy of the ball

1. Gather materials 2. Find the mass of the can 3. Measure height of the can 4. Drop the ball onto the can from 0.5m from the table 5. Take a can that is not crushed, and trace it on a piece of paper 6. Take the can that is crushed, and trace it on top of the sketch that you made in step 5 7. Find the length of the crush 8. Divide the crush into 9 different zones 9. Find the width of the zones 10. Find crush energies of each 11. Add the energies to get the total crush energy
 * __Procedure__**:

Data Table 1: Crush Energy of Zone 1-9
 * __Data__**:

Data Table 2: Data of the Can

Calculations: (Trial 1) CE= (A^2/2B)(L) + ACL +(BC^2/2)(L) = (77^2)/(2*37)(0.0295) +(77*0.1181*0.295) +(37*0.1181^2)/(2*0.295) =26.39 ft*lbs = 35.79 Nm

Theoretical velocity PE1=KE+PE2 mgh=0.5mv^2+mgh (9.8)(0.5) = 0.5v^2+(9.8)(0.071) v = 2.84m/s

Actual velocity CE = KE + PE 363.76 = 0.5mv^2 363.76 = 0.5(0.066)(v^2) v = 104.99m/s

Percent Error = (2.84-104.99)/(2.84)*100 =

=Reaction Time Lab=

Data
Data Table: Reaction Time

Calculations (using Trial 1)
To find time: d = (0.5)(a)(t^2) 0.08 = (0.5)(9.8)(t^2) t = 0.128s PRT = 1.28s