Question:-
The model of a propeller, 3 m in diameter, cruising at 10m/s in air, is tested in a wind tunnel on a 1:10 scale model. If a thrust of 50 N is measured on the model at 5 m/s wind speed, then the thrust on the prototype will be
Option (A)
20,000 N
Option (B)
2,000
Option(C)
500 N
Option(D)
200N
Correct Option:
(A)
Question Solution:
(Thrust of model / Thrust of prototype) = (rv2.d2)model / (rv2d2)prototype
(50/Fp) = (5/10)2(1/10)2
Fp = 20,000N
question-answer-faq-2766