A propeller, initially at rest, rotates about its midpoint with an angular acceleration of 12 rad/sec2. How much time will it take to rotate through a 90 deg angle?

Consider the following problem: a box with an open top is to be constructed from a square piece of cardboard, 3 ft wide, by cutting out a square from each of the four corners and bending up the sides. find the largest volume that such a box can have.

Write maxwell's equations and discuss the terms involved and the results of each equation in classical electrodynamics. if it is possible to write these equations in integral form, give the integral forms. find the wave equation for electromagnetic waves from the maxwell equations. what is the propagation velocity of electromagnetic waves in space according to the wave equation you find?

Consider a hydrogen atom in the ground state. what is the energy of its electron? =e= jj now consider an excited‑state hydrogen atom. what is the energy of the electron in the =5n=5 level? =e5= j