Show a sketch of a galvanic concentration cell. Each compartment consists of a Co electrode in a Co(NO3)2 solution. The concentrations in the compartments are 2.0 M and 0.10 M, respectively. Label the anode and cathode compartments. Show the direction of electron flow. (a) Calculate the Ecell at 25C. (b) What are the concentrations in the compartments when the Ecell drops to 0.020 V? Assume volumes to remain constant at 1.00 L in each compartment.
CJ 355 Criminalistics: Vehicle accidents 3/24/16 12:06 PM Vehicle incidents • After a motor vehicle accident occurs, it will usually be investigated and reconstructed • Traffic accidents resulting in fatal or nonfatal personal injury to any person or damage to the vehicle rendering the vehicle inoperable, should be reported to the nearest law enforcement officer having jurisdictions. • Safety must be emphasized at all times • Investigators look for signs of speeding, mechanical violations, alcohol/drug usage, etc. • Must determine how the accident occurred, who or what caused the accident, and why the accident occurred Steps to an investigation • Arrival at the scene o While en route to the scene, the officer should obtain the following information § Location § Time of notification § Who notified the officer and how § Weather and visibility conditions § General information regarding the seriousness of the accident § Whether or not additional support is headed to the scene • Position of the patrol vehicle o Patrol vehicle should be positioned as to not cause further traffic congestion or accidents § If necessary, vehicle may be used as a roadblock § At night, the headlights should illuminate the entire scene o Emergency lights should be on at all times • Triage and securing the scene o Investigations should determine the extent of injuries (if any), render firat aid, and request medical assistance o Order of triage § Children on roadway § Children in vehicle § Adults on roadway § Adults in vehicle § Prioritized by severity of injuries o Severely injured persons should not be moved EXCEPT to preserve their safety o Positions of victims should be noted for report purposes § If on the road, the positions should be outlined in chalk or road paint AFTER THE INDIVIDUAL IS MOVED o After caring for the injured, the scene should be secured to protect property and preserve evidence • Establish traffic control o Reroute vehicles o Keep spectators or unnecessary personnel away from the accident • Request additional support (electric, road, water, medical, etc.) • Moving vehicle and marking wheels o Under the following conditions, a vehicle must be moved immediately § When an injured person is trapped in the wreckage and cannot be treated there § When a person is trapped in wreckage near burning material or an area of a potential fire hazard § When a vehicle position is an immediate hazard to oncoming traffic and adequate traffic control cannot be established • Inspection of accident site o Determine whether there has been a violation of the law o Identify and preserve fragile evidence § Any fragile evidence that can be damaged, altered, destroyed or removed from the scene must be identified and secured § Prior to removal, the position must be noted and photographed o Take statements o Measurements taken of evidence left by the vehicles by electric surveying equipment § Point of Impact § Final resting positions § Skid marks § Scrub marks § Gouge marks • Vehicle inspections o Vehicle condition § Any physical characteristics of the vehicle existing prior to the accident o Damage profile of vehicles § Vehicle damage: resulting physical characteristics of the vehicle caused by the accident ú Contact: that which occurs as a direct result of contact with or y an object ú Induced: that while resulted from the shock of the collision § Inspection of brakes, steering tires, and suspension § Position of turn signal level and lights § Presence of drugs and/or alcohol • Importance of documentation o Sketches § Help explain the accident § Help the investigator reveal facts § Locate any given point at the scene § Serve as the basis for accurate scale drawing 3/24/16 12:06 PM 3/24/16 12:06 PM