Question

6. Convert the following into Si units 2.18 weeks 287 in2 3.93 mph 7. Which gives a better order of magnitude calculation of final velocity of a rocket starting at rest, accelerating at a rate of 9.80 m/s2 for a distance of 197 km? (only one answer here) a. 100 m/s b. 200 m/s c. 1000 m/s d. 2000m/s A marching band player walks directly north at a speed of 2.50 m/s for a time of 12.0 seconds, turns 35.0° to the east and walks at half that speed for another 15.0 seconds 8. average velocity for the entire trip?

Answer 1

2 . 18 weeks = 2 . 18 times 7 days = 2 . 18 times 7 times 24 hours = 2.18 times 7 times 24 times 60 minutes = 2 . 18 times 7 times 24 times 60 times 60 seconds = 1318464 seconds = 1 . 32 times 10^6 s 287 in^2 = 287 times (0 . 0254m)^2 = 0 .1852 m^2 3 .93 mph = 3 .93 times 1 .61 km/hr = 3 . 93 times 1000 m/3600 sec = 1 . 09 m/s Given initial velocity u = 0, g = 9 .8 m/s^2 distance s = 197 km = 197 times 110^3 m, final velocity u = ? So, from Newton � s third equation of motion v^2 = u^2 + 2 gs = 0 +