Consider a NACA 0012 aerofoil of chord $c$ in a freestream with velocity $V_{\infty}$ at a non-zero positive angle of attack $\alpha$. The average time-of-flight for a particle to move from the leading edge to the trailing edge on the suction and pressure sides are $t_{1}$ and $t_{2}$, respectively. Thin aerofoil theory yields the velocity perturbation to the freestream as $V_{\infty} \frac{(1+\cos \theta) \alpha}{\sin \theta}$ on the suction side and as $-V_{\infty} \frac{(1+\cos \theta) \alpha}{\sin \theta}$ on the pressure side, where $\theta$ corresponds to the chordwise position,
$x=\frac{c}{2}(1-\cos \theta) .$ Then $t_{2}-t_{1}$ is
(A) $-\frac{8 \pi \alpha c}{V_{\infty}\left(4-\pi^{2} \alpha^{2}\right)}$
(B) 0
(C) $\frac{4 \pi \alpha c}{V_{\infty}\left(4-\pi^{2} \alpha^{2}\right)}$
(D) $\frac{8 \pi \alpha c}{V_{\infty}\left(4-\pi^{2} \alpha^{2}\right)}$

Question ID - 155732 :-

Consider a NACA 0012 aerofoil of chord $c$ in a freestream with velocity $V_{\infty}$ at a non-zero positive angle of attack $\alpha$. The average time-of-flight for a particle to move from the leading edge to the trailing edge on the suction and pressure sides are $t_{1}$ and $t_{2}$, respectively. Thin aerofoil theory yields the velocity perturbation to the freestream as $V_{\infty} \frac{(1+\cos \theta) \alpha}{\sin \theta}$ on the suction side and as $-V_{\infty} \frac{(1+\cos \theta) \alpha}{\sin \theta}$ on the pressure side, where $\theta$ corresponds to the chordwise position,
$x=\frac{c}{2}(1-\cos \theta) .$ Then $t_{2}-t_{1}$ is
(A) $-\frac{8 \pi \alpha c}{V_{\infty}\left(4-\pi^{2} \alpha^{2}\right)}$
(B) 0
(C) $\frac{4 \pi \alpha c}{V_{\infty}\left(4-\pi^{2} \alpha^{2}\right)}$
(D) $\frac{8 \pi \alpha c}{V_{\infty}\left(4-\pi^{2} \alpha^{2}\right)}$

We hope we have given the updated helpful answer / content for your query in an easily accessible format to help you in preparing adequately.
We do offer free support materials, 11th maths guide 11th maths guide12th maths guide10th maths guide, also for all the classes books and guide to all the students who sign up for SaraNextGen. Apart from traditional textbook queries, we've got conjointly provided further high order level thinking issues, that are seemingly to be expected in boards and competitive exams. It includes conceptual queries, MCQs, Long and short answer type queries, etc. These Questions are designed to learn each student and academics by providing chapter-wise further issues focusing totally on testing conceptual information with applications.
Here, we've got provided a number of the necessary ways in which within which the solutions of all the Questions will profit students of class 1 to 12. If you have any queries,
drop a message to us and we will get back to you at the earliest.