2. Chevy is fast! How about BMW? NJIT Physics 1: Distance, time and how we measure them are basic to understanding motion. 2015 Chevy Corvette Z06 2015 BMW M1 Concept Car

3. How fast did my Chevy go in m/s? I was travelling in a fast Chevy in the desert. I timed the car going 4 miles in a minute, but my accuracy was only about 2% in each measurement because I used a mile marker and a hand timer. I told a friend from Europe, and she said it was no big deal. She had gone 100m/s in her much faster BMW. In her standard units what was my Chevy’s speed? Carcabin.com

4. Step by step solution: 1.Sketch 2.Convert x and t to standard units: 3. Write the physics equation: 4.Do the math: 5.Estimate the uncertainty: 6.Comment on the numbers: 60sec=1min 1609m=1mi 2.24mi/hr=1m/s

5. Use the step by step method To answer the question

6. Step by step solution: 1.Sketch 2. Convert x and t units: x=4mi*[1609m/1mi]=6436m t=1.0min*[60sec/1min]=60s 3. Physics: v=(x-xo)/t 4.Math: v=6436/60s=108m/s 5.Uncertainty: 2% in x; 2% in t; ~4% in v; v is probably between 100 and 116 m/s 6.But not really faster than the claim of v=100 for the BMW. 7.Comment: The Chevy’s measured speed is fast: 108m/s*[2.24mi/hr]/[1m/s]=240mi/hr! xo=0 x=4miles to=0 t=1min

7. Homework: Calculate when you have to leave home in order to get to class on time. Read the part of chap 1 on x, t, v and units Make a description of your trip from home to this class in terms of x, t, and the average v for segments of your trip where your v is roughly constant. E.g. walking, driving in local traffic, driving on freeways. Convert to standard units Estimate the uncertainties Hand in a written report at next class. Also figure out when you have to leave home to get to class on time?