Fun fact: the average car length is 14.7 ft, (15 ft to 2 significant figures.)

Just for fun, let 1 car 14.7 feet and convert 1 car/s to miles per hour:

That's very convenient. In other words, to convert to , divide by 10, for example,

You are in the red car in the figure to the right, traveling 30 miles/hour in a residential neighborhood. Six car lengths in front of you a young boy is on his bicycle, heading to his friend's house across the street. At that moment you get a text message. It takes you 2 seconds to check who it is from (about average - try it after the quiz.)

Where is the front of your car when you are no longer distracted?

Question

Fun fact: the average car length is 14.7 ft, (15 ft to 2 significant figures.)

Just for fun, let 1 car  14.7 feet and convert 1 car/s to miles per hour:

That's very convenient.  In other words, to convert  to , divide by 10, for example,

You are in the red car in the figure to the right, traveling 30 miles/hour in a residential neighborhood.  Six car lengths in front of you a young boy is on his bicycle, heading to his friend's house across the street.  At that moment you get a text message.  It takes you 2 seconds to check who it is from (about average - try it after the quiz.)

Where is the front of your car when you are no longer distracted?

BlackTom AI · Accepted Answer

Before delving into choices, note that the provided data for this question is incomplete: the answer options list contains only "A" and the answer_options field is empty. Without the full set of options to compare, we cannot definitively state which option is correct. What we can do is show how you would approach solving the underlying physics/geometry problem if the visual labels (A, B, C, D) correspond to specific front-rear positions along the street.

First, convert the car’s speed to a consistent unit for distance over time. At 30 miles per hour, the speed in feet per second is 30 miles/hour × 5280 feet/mile ÷ 3600 seconds/hour ≈ 44 feet/second. This gives a usable scale for both reaction distance and braking considerations.

Second, compute the distance traveled during the driver’s reaction time. If the driver takes 2 seconds to check the message, the car covers about 44 ft/s × 2 s ≈ 88 feet before any braking begins. This 88-foot reaction gap is critical in determining whether the front of the car would still be safely behind the bicycle and the boy after distraction ends.

Third, relate the given “six car lengths” figure to the numerical data. A single car length is given as 14.7 feet (to two significant figures, 15 ft). Six car lengths would be 6 × 14.7 ft ≈ 88.2 feet. This aligns very closely with the 88 feet traveled during a 2-second distraction at 30 mph, suggesting the problem is crafted so that the distance the car travels during reaction time corresponds to six car-lengths, i.e., the front of the car has moved forward by about one vehicle length per car length counted along the road.

Fourth, consider how to determine the front-of-car position when you are no longer distracted. If the front of the car was originally at a given labeled point (e.g., A, B, C, D) and you must account for the 88-foot advance during the distraction, you would shift your position forward by that 88 feet along the road. The correct option would be the label that corresponds to the position 88 feet ahead of the original front position, assuming the labels A–D indicate equidistant points along the lane.

Fifth, possible misconceptions to avoid:
- Assuming the entire 88-foot displacement represents stopping distance instead of reaction distance. The initial 88 feet is before braking begins; additional distance is needed to come to a stop after braking starts.
- Thinking that the six-car-length figure exactly equals the stopping distance; it actually matches the reaction distance if each car length is taken as 14.7 feet.
- Ignoring the bicycle and the boy as a moving target; a rider on a bicycle introduces a dynamic obstacle that requires considering the safe stopping distance and space to avoid a collision.

If you can provide the full set of answer options or label mappings for A, B, C, and D (i.e., which physical position on the image each label corresponds to), I can map the calculated 88-foot reaction shift to the correct option and explain precisely why that option is correct and why the others would be incorrect.

In summary, with the data given, the central calculation shows about 88 feet of forward travel during the 2-second distraction, which matches six car lengths. The correct choice would be the label that corresponds to the position 88 feet ahead of the car’s original front position, after the distraction ends. However, due to the missing option details, a definitive choice cannot be announced here.

PHYS 1, Section 001: Science of Phys (22581--HB---P-PHYS----1---------001-) Quiz - Section 1.2

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