Aspring is stretched to a displacement of 3.4 m from equilibrium. then the spring is released and allowed to recoil to a displacement of 1.9 m from equilibrium. the spring constant is 11 n/m. what best describes the work involved as the spring recoils?

Aperson stands on a platform, initially at rest, that can rotate freely without friction. the moment of inertia of the person plus the platform is ip. the person holds a spinning bicycle wheel with its axis horizontal. the wheel has moment of inertia iw and angular velocity ωw. take the ωw direction counterclockwise when viewed from above. part a what will be the angular velocity ωp of the platform if the person moves the axis of the wheel so that it points vertically upward?

James is trying to prove newton's 2nd law of motion. he tries to move four different objects with different masses, shapes, and sizes from point a to point b. the objects are a toy car, a car, a refrigerator, and a kitchen table. after some experimentation, he finds that force is dependent on the mass of the object, rather than it's size or shape. the object that takes the most force to move is the

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.