Amass weighing 32 lb stretches a spring 4 ft. the mass is attached to a viscous damper with a damping constant of 4 lb2s/ft. the mass is pushed upward, contracting the spring a distance of 1 ft, and then set in motion with a downward velocity of 4 ft/s. (a) determine the position y of the mass at any time t. (b) find the (or quasi) frequency, period, phase and amplitude of the motion, that is to find wo, t, δ and r from y(t) = rect cos(wot-5). (c) if there is an external force of f(t) 26et lb, in m" ky f(t), what is the general solution (not considering the initial condition)?

the answer is to check all of them! they all apply well at least i think so!

no simpler subs form complex ones. synthesise = make

c because the news are a source of information of things that happen on the daily and shows evidence about that particular topic

speed of light in vacuum is 300,000 km/s

speed of light in other mediums is given by the expression v = c/n, where c is the speed of light in vacuum and n is the refractive index of medium.

for the first medium v = 200,000 km/s

  so, refractive index of medium = 300000/200000 = 1.5

    1.5 refractive index is usually for glass. so first medium is glass.

for the second medium v = 250,00 km/s

so, refractive index of medium = 300000/250000 = 1.2

    1.2 refractive index is usually for water. so second medium is water.

for the third medium v = 0 km/s

so, refractive index of medium = 300000/0 = ∞

    ∞ refractive index is usually for opaque mediums. so third medium is opaque medium.