InterviewSolution
Saved Bookmarks
InterviewSolution
| 1. |
An athlete in the Olympic gamed covers a distance of `100 m` in `10 s`. His kinetic energy can be estimated to be in range. (1) `200 J - 500 J` (2) `2 xx 10^(5) J - 3 xx 10^(5) J` (3) `20,000 J - 50,000 J` (4) `2,000 J - 5,000 J`.A. `200 J - 500 J`B. `2 xx 10^(5) J - 3 xx 10^(5) J`C. `20,000 J - 50,000 J`D. `2,000 J - 5,000 J`. |
|
Answer» Correct Answer - D average velocity `v_(av) = (s)/(l) = (100)/(10) = 10 m//s` Assuming an athelete has mass about `50` to `100 kg` or average mass `75 kg`, His average kinetic energy. `k_(av) = (1)/(2) mv_(av)^(2) = (1)/(2) xx 75 xx 100 = 3750 J` Minimum possible kinetic energy, `(for 50 kg)` `k_(min) = (1)/(2) mv_(av)^(2) = (1)/(2) xx 50 xx 100 = 2500 J` Maximum possible kinetic energy `(for 100 kg)` `k_(max) = (1)/(2) mv_(av)^(2) = (1)/(2) xx100xx100 = 5000 J` Hence the kinetic energy could be in the range `2000` to `5000 J`. |
|