Amass of 20 g stretches a spring 5 cm. suppose that the mass is also attached to a viscous damper with a damping constant of 400 dyn·s/cm. if the mass is pulled down an additional 2 cm and then released, find its position u at any time t. plot u versus t. determine the quasi frequency and the quasi period. determine the ratio of the quasi period to the period of the corresponding undamped motion. also find the time τ such that |u(t)| < 0.05 cm for all t > τ.

Identify the theory that can be used to explain each phenomenon. answers diffraction: wave theory interference: wave theory reflection: both particle and wave theories refraction: both particle and wave theories

Balloon a has charge q, and identical mass balloon b has charge 10q. you hang them from threads near each other. choose all of the statements with which you agree. check all that apply. a. a and b exert the same magnitude forces on each other. b. the force that a exerts on b is 10 times the force that b exerts on a. c. the angle between the thread supporting a and the vertical is < the angle between the thread supporting b and the vertical. d. the force that a exerts on b is 1/10 the force that b exerts on a.

What pressure difference is required between the ends of a 2.0-m-long, 1.0-mm-diameter horizontal tube for 40 c water to flow through it at an average speed of 4.0 m/s?