At the same time the girl is pushing the box, a boy is trying to straighten out an extension cord. While doing this, he sends a pulse through the cord traveling at the exact same speed as the box (11 m/s). If the pulse has a length of 0.75 meters, calculate its frequency.

The slotted link is pinned at o, and as a result of rotation it drives the peg p along the horizontal guide. compute the magnitude of the velocity and acceleration of p along the horizontal guide. compute the magnitudes of the velocity and acceleration of p as a function of θ if θ=(3t) rad, where t is measured in seconds.

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.

The diagram shows four locations in the electric field of a positive point charge m. at which location is the electric potential the greatest.