. Two isolated conducting spheres are separated by a large distance. Sphere 1 has a radius of 20 cm and an initial charge30 nC while Sphere 2 has a radius of 60 cm and an initial charge 70 nC. A very thin copper wire is now connected to thespheres to allow charge to flow between them. How much charge will be transferredfromSphere 2toSphere 1? (Notethat the charge transferred can be positive, negative or zero.)

Ahot wire operates at a temperature of 200°c while the air temperature is 20°c. the hot wire element is a tungsten wire of 5 um diameter and 2 mm in length. plot using excel current, heat transfer and heat generated by the wire for air velocity varying from 1-10 m/s in steps of lm/s? matlab the sensor voltage output, resistance, or assume nu 0.989 re033pr13 take air properties at tr (200°c20°c)/2 = 110°c properties of tungsten: c 0.13 kj/kg.k 3 p 19250 kg/m k (thermal conductivity) = 174 w/m.k

Starting wih an energy balance on a rectangular volume element, derive the one- dimensional transient heat conduction equation for a plane wall with constant thermal conductivity and no heat generation.

Heat transfer by is the fastest mode of heat transfer that requires no intervening medium. a)-conduction b)-convection c)-radiation d)-conduction and convection