Machine-translated by Google. Questions are authored in English.
Top

Discussion

Air at \( 30 \) m/s meets a smooth plate. Taking transition at \( Re = 5 \times 10^5 \), how far back does it occur?

  • A.2.45 m
  • B.0.0245 m
  • C.1.00 m
  • D.0.245 m

Answer: D

Rearranging, \( x = Re\,\mu/(\rho V) = 5 \times 10^5 \times 1.8 \times 10^{-5} / (1.225 \times 30) = 9/36.75 = 0.245 \) m. Roughly the first quarter-metre is laminar and everything downstream turbulent, which is typical for air at ordinary speeds.

No comment is present. Be the first to comment.
Loading…

Post your comment

Please log in or register to post a comment.