Taipei 101 (a 101-story building in taiwan) is sited in an area that is prone to earthquakes and typhoons, both of which can lead to dangerous oscillations of the building. to reduce the maximum amplitude, the building has a tuned mass damper, a 660,000 kg mass suspended from 42 m long cables that oscillate at the same natural frequency as the building. when the building sways, the pendulum swings, reaching an amplitude of 75 cm in strong winds or tremors. damping the motion of the mass reduces the maximum amplitude of the oscillation of the building. a. what is the period of oscillation of the building? b. during strong winds, how fast is the pendulum moving when it passes through the equilibrium position?

The ultracentrifuge is an important tool for separating and analyzing proteins. because of the enormous centripetal accelerations, the centrifuge must be carefully balanced, with each sample matched by a sample of identical mass on the opposite side. any difference in the masses of opposing samples creates a net force on the shaft of the rotor, potentially leading to a catastrophic failure of the apparatus. suppose a scientist makes a slight error in sample preparation and one sample has a mass 10 mg larger than the opposing sample. if the samples are 12 cm from the axis of the rotor and the ultracentrifuge spins at 70,000 rpm, what is the magnitude of the net force on the rotor due to the unbalanced samples? ( be thorough on your answer)

The illuminance of a surface varies inversely with the square of its distance from the light source. if the illuminance of a surface is 120 lumens per square meter when its distance from a certain light source is 6 meters, by how many meters should the distance of the surface from the source be increased to reduce its illuminance to 30 lumens per square meter?

Resistivity of a material is the resistance of a cm long sample of the material of 1 cm2 cross-sectional area.