Q1. In a parallel plate electrode system, the electrode separation d = 2 mm, the electrode surface area S = 4 cm2
, relative permittivity of the insulator εr = 1 (air) and the applied voltage, U = 5
kV. Where the breakdown electric stress of the insulator (air) is 30 kV /cm.
a) Determine the capacitance, electrical charge, electric field strength, electrical flux
density of the system,
b) Find the surface charge density and the maximum voltage that can be applied to the
system without any discharge.

Aloaded platform of total mass 500 kg is supported by a dashpot and by a set of springs of effective stiffness 72 kn/m. it is observed that when the platform is depressed through a distance x = 12.5 cm below its equilibrium position and then released without any initial velocity; it reaches its equilibrium position in the shortest possible time without overshoot. find the position and velocity of the loaded platform 0.10 sec. after its release. if a further load of 400 kg is added to the platform, find, i) the frequency of damped vibrations, and i) the amplitude of vibration after 2 complete oscillations, given that the initial amplitude is 15 cm.

The filament of an incandescent lamp has a temperature of 2000k. calculate the fraction of radiation emitted in the visible light band if the filament is approximated as blackbody

Vibration monitoring this technique uses the noise or vibration created by mechanical equipment and in seme cases by plant systems to detemine their actual condtion. a)- true b)- false