For scientist

Could it be possible to run at the speed of sound with some future tool

The ratio of lift to drag l/d for a wing or airfoil is an important aerodynamic parameter, indeed, it is a direct measure of the aerodynamic efficiency of the wing. if a wing is pitched through a range of angle of attack, l/d first increases, then goes through a maximum, and then decreases. consider an infinite wing with an naca 2412 airfoil. estimate the maximum value of l/d. assume that the reynolds number is 9x10^6.

Which sound characteristic is not affected by the relative motion of an object

Select the three ways that the parallel-plate capacitor differs from a car battery.