# Science Physics

Topics: Crash test dummy, Tram accident, Injury Pages: 6 (2104 words) Published: November 5, 2012
CRASH TEST DUMMIES STUDENT REPORT
Practical Report Grading Name: Emily Parker GRADE| A| B| C| D| E|
PART A & B AIMS(*)| Formulation of questions explicitly linked to science knowledge| Formulation of questions informed by science knowledge | Formulation of questions that can be investigated scientifically| Statements of questions | Safe, directed use of equipment in given investigations| PART B METHOD(*)| Concise description of methods designed to control and accurately measure variables and systematically collect data, | Description of methods designed to control and accurately measure variables and systematically collect data, | Description of methods designed to control and measure variables and collect data, | Description of methods used to collect data in given investigations| | PART A , B & SURVEYANSWERS TO QUESTIONS (***)| Comprehensive analysis of trends in data to explain relationships between variables and to develop justified conclusions| Significant analysis of trends in data to describe relationships between variables and to develop supported conclusions| Analysis of trends in data to identify relationships between variables and to develop conclusions | Description of trends in data and statements of conclusions| Listing of data and superficial statements of conclusions| COMMENT

PART A: AIM
The purpose of this experiment is to use dynamic trolleys and plasticine dummies to model the effect inertia has on the impact of a car accident. RESULT:
TROLLEY A DUMMY| The dummy in trolley A was propelled forward when it collided with trolley B.| TROLLEY B DUMMY| When trolley A hit trolley B the dummy in trolley B was jolted backward when the trolley stopped all of the sudden.|

1. What happens to the dummy on trolley A during the collision? Explain why this happened. The dummy in trolley A slid forward slightly as the trolley moved down the ramp. This displays how inertia allows the dummy to move forward even without being pushed directly. When the trolley collided with trolley B the dummy was thrown forward and landed in front of the collision. The fact that the dummy continued to travel forward also displays the principle of inertia. 2. What happens to the occupants of a moving car when it collides with a stationary car? The occupant of a moving car that has just collided with the back of another car would usually be thrown forward due to the principle of inertia. This is why most modern cars have seatbelts and airbags. By having these safety features the unfulfilled momentum caused by the sudden stop is not so harmful. 3. What design features of a car reduce the risk of injury in this type of collision? Brakes would be the most successful way of preventing injury but if the accident is unpreventable a seat belt would prevent the occupant from being thrown forward and hitting their head on the steering wheel or windscreen. Air bags would also prevent this from happening by adding a cushion like surface for the occupant to land on. If the occupant were to hit their head on the steering wheel or smash the windscreen the results could be fatal. 4. What happened to the dummy on trolley B? Explain why this happened. When trolley A hit the back of trolley B the dummy in Trolley B was also jolter backwards and off of the trolley. The force of the other trolley pushed trolley B out from underneath the dummy causing it to land behind the impact of the collision. 5. What happens to the occupants of a stationary car hit from behind by another car? If a car travelling down a hill was to hit a stationary car the occupants of the stationary car would be jolted forward by the initial impact then thrown backwards depending on the force of the collision. This is because the car was pushed forward unexpectedly and the body would have been forced back against the chair....