(a) an object of mass 0.2 kg is hung from a spring whose spring constant is 80 n/m and allowed to oscillate. the object is subject to a resistive force given by -bv, wherc u is the objects velocity in metres pcr second (i) if the damped frequency is 0.995 of the undamped frequcncy, what is the value of the damping constant b? (6) (ii) by what factor is the amplitude of the oscillation reduced after 4 complcte cycles?

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.

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