Teaching Physics with the Physics Suite Edward F. Redish Problems Sorted by Type | Problems Sorted by Subject | Problems Sorted by Chapter in UP

Hanging mass on a spring

 A cylinder is hung from a spring that is attached to a frame as shown in the figure at the right. Use the coordinate system with an origin (y = 0) at the base of the frame , and the upward direction taken to be positive. The cylinder is shown at rest at its equilibrium position, y0. The cylinder is pulled downward a very small amount and released. At the instant the cylinder passes its equilibrium position for the first time, a clock is started (t = 0). a) On the axes below, sketch a graph of the velocity of the mass vs. time, vy vs. t. (The axes cross at the origin - the point (0,0).)

b) Write an equation that gives y as a function of time corresponding the vy vs. t graph you sketched above.

c) At the instant of time when the cylinder is passing its equilibrium position, what forces are acting on the cylinder and in what directions do they act?   If there is more than one, indicate their relative magnitudes.