Marinich+Chapter+3+Wiki

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Section 1

What do you think?
The things that you can do to prevent getting seriously hurt during a car accident are: wear your seatbelt, and make sure that your air bag is working properly.

Investigate: (yes/no) ** || (1,2,3) ** || == **Physics Talk Summary:** Four wheel drive crashes are due to: growing number of kilometers travel and the tendency to increase speed under the impression that safety features will protect. If you are in an accident in a safer vehicle, the chances of injury are limited. ==
 * Safety features ** ||
 * Means of protection ** ||
 * Pre-1960 cars
 * Pre-1960 cars
 * New Cars
 * **seat belts** || **Keeps you in the seat after you get in an accident.** || **No** || **1** ||
 * **head restraints** || **Keeps your head from snapping back.** || **No** || **1** ||
 * **front airbags** || **Keeps you from smashing into the dashboard.** || **Yes** || **1** ||
 * **back up sensing system** || **Shows if you are backing up into anythings.** || **No** || **2** ||
 * **front crumple zones** || **Increase collision distance.** || **No** || **1,2** ||
 * **rear crumple zones** || **Increase collision distance.** || **No** || **2** ||
 * **side-impact beams in doors** || **Resists side penetration.** || **No** ||  ||
 * **shoulder belts for all seats** || **Keeps you from jolting forward.** || **Yes** || **3** ||
 * **anti-lock braking systems (ABS)** || **Helps maintain control.** || **No** || **2** ||
 * **tempered shatterproof glass** || **Helps prevents cuts.** || **Yes** || **1** ||
 * **side airbags** || **Protects head in collision.** || **No** || **2** ||
 * **turn signals** || **Warns other driver of actions.** || **Yes** || **1** ||
 * **electronic stability control** || **Helps resist roll overs** || **No** || **2,3** ||
 * **energy-absorbing collapsible steering column** || **Prevents chest trauma** || **No** || **1** ||

**Checking Up:**
= 1) Three ways that car safety has improved since the 1960s are side airbags, head restraints and shoulder belts. = = 2) Two explanations for 4WD accidents are because of the growing number of kilometers travled and the tendency to increase speed under the impression that safety features will protect. = = =

**Physics To Go:**
= 1) S, F, R, S, F, R, F, S, T . = = 2) Helmet, shoulder pads, knee pads, and sneakers. = = 3) Helmet, shoulder pads, high socks, knee pads, and wrist pads = = 4) Helmet, shoulder pads, knee pads, pants, and sneakers. = = =

**What Do You Think Now:**
= To protect oneself from serious injury in an accident you need to wear your seatbelt and make sure all safety precautions in the car are working effectively. If not in a car, one needs to wear all the protective gear recommended to save from any broken bones or bad bruising. =

=Section 2=

Investigate 2

Hypothesis: 1) When a passenger is wearing his/her seatbelt they get less sever injuries because the seatbelt will keep them in the seat. If they are not wearing their seatbelt then then might fly forward into the wind shield. 2) The passengers safety after the collision depends on how much damage is done to the car and the how fast the ambulance and people who are going to help the person come to the crash. 3) Seat belts in a race car would need to be less lenient and tighter to keep the driver in place if there is a crash because the race car is going a lot faster.


 * **//Type of Seatbelt//** || //**Before Picture**// || //**After Picture**// || //**Description and Observations**// || //**Group**// ||
 * Thread ||  ||   ||   ||   ||
 * Wire ||  ||   ||   ||   ||
 * String ||  ||   ||   ||   ||
 * Yarn ||  ||   ||   ||   ||
 * Ribbon ||  ||   ||   ||   ||
 * Rubber Bands ||  ||   ||   ||   ||

**5)** Thick and strong materials that cover more parts of your bodies. They work better because it's more force against you to keep you in your seat.
=== **6)** First Collision: The automobile strikes an object (pole/wall etc), the object exerts the force that brings the automobile to rest. - Second Collision: When the automobile stops, the body keeps moving. The structure of the automobile exerts the froce that brings the body to rest. On the third collision, the body stops, but the heart, the brain, and other organs keep moving. The body wall exerts the force that brings the organs to rest. ===

Conclusion:
=== **1)** The seatbelt restricts the passengers of a car so when the car gets into a crash the passenger stays in their seat and stays safe. The thickness of the belt and the areas of the body that the belt cover affect the effectiveness of a seatbelt. When designing a seatbelt for a race car you need to consider how fast the car is going and how sharp the turns that the car is making. ===

**3)** I would repeat the experiment 3 times and have each person use the same amount of books so our results all come form the same incline of the ramp.
=Section 3=

Investigate 3

An airbag would protect you during an accident by creating a cushion for if you are jolted forward during an accident.

=Section 7=

Investigate 7: Impulse and the Crumple Zone
// Objective: A crumple zone is part of the body of a car that compresses during an impact. It absorbs the energy of the collision and lessens the force on the passengers. //
 * What are some of the factors that car designers and engineers must consider when designing a crumple zone as a safety feature?
 * You have to make sure that it can absorb impact but also you have to make sure that it doesn't have too much give so that it is not sturdy.
 * What enables a passenger to survive a collision?
 * Wearing a seatbelt and having the proper safety features in a car such as air bags.
 * What does a Force vs. Time graph look like for a collision?
 * What would the Force vs. Time graph look like if the collision was more safe?

// Materials: List any materials used and draw a labeled diagram of your set-up (alternatively, include a snapshot or video). //

//Procedure:// // 1. On the floor, place a ramp on a stand so that one end is raised 10-cm and the other end is 20 cm from the wall. // // 2. Place a block in the cart and attach a 2-cm piece of masking tape to the front of the block and down onto the cart. Place the cart at the top of the ramp and release it. Record your observations. // // 3. Design a crumple zone to protect the block from tipping over. You can use only the following materials: one sheet of paper, 30-cm tape, 2 rubber bands, and 30-cm of string. Record your design(s) and the changes you make to it in a data table. You may want to use the available technology (still pictures and video) to supplement your written descriptions. // // 4. Measure the mass of your cart with apparatus attached. // // 5. Once you have a functional design that you are happy with, you will bring it to the front of the room to test. You will allow your cart to crash into a force sensor in order to generate a force vs. time graph, while a motion detector will measure the speed of the cart. // // 6. Click the ∑ button to get the area of the F-t Graph. Click the smart tool to get the velocity of the cart before and after the collision. // // 7. Repeat 3 times. //


 * Data and observations:** Add more columns/row as needed.
 * **Trial** || **Mass of Cart with apparatus(kg)** || **Speed of Cart** before collision(m/s) || **Speed of cart after collision (m/s)** || **Area on F-t graph (Ns)** || **Change in momentum (kgm/s)** || **Impulse (Ns)** ||
 * No Crumple Zone (teacher) ||  ||   ||   ||   ||   ||   ||
 * #1 with CZ ||  ||   ||   ||   ||   ||   ||
 * #2 with CZ ||  ||   ||   ||   ||   ||   ||
 * #3 with CZ ||  ||   ||   ||   ||   ||   ||

**Calculations:** Show equation(s), numbers plugged in, and answer with correct units. Add columns in your data table to include these results. 1. Calculate the change in momentum for your cart. 2. Impulse is equal to the area of the F-t graph. What is the impulse experienced by your cart?

***Read the Physics Talk p324 - 329 before answering the following questions.** *

1. Define the following terms: velocity, acceleration, Newton’s second law of motion, and momentum, impulse. 2. What is a crumple zone? 3. Why is it safer to collide with a soft cushion than a hard surface? 4. What is the relationship between impulse and change in momentum? 5. How is the impulse-momentum relationship related to Newton’s second law? 6. What were the key features of your crumple zone and why were they important? 7. What happened to the area of the Force-time graph as we increased the speed of the cart? 8. What happened to the area of the Force-time graph when the collision was inelastic vs. elastic?
 * Questions:**

**Conclusion:** · What are some of the factors that car designers and engineers must consider when designing a crumple zone as a safety feature? Compare and contrast crumple zones and air bags. · Explain at least 1 cause of experimental error. Be sure you describe a specific reason. · How would you improve the results of this lab? (In other words, what would you change about the materials or procedure to eliminate or reduce the experimental error you describe above?)