A circular ring of charge of radius a lies in the x-y plane and is centered at the origin. Assume also that the ring is in air and
carries a uniform density pℓ.

(a) Show that the electrical potential at (0, 0, z) is given by V = pℓa/[2ƹ0(a2 + z2)1/2].
(b) Find the corresponding electric eld E

Liquid flows at steady state at a rate of 2 lb/'s through a pump, which operates to raise the elevation of the liquid 100 ft from control volume inlet to exit. the liquid specific enthalpy at the inlet is 40.09 btu/lb and at the exit is 40.94 btub. the pump requires 3 btu/s of power to operate. if kinetic energy effects are negligible and gravitational acceleration is 32.174 tt/s, the heat transfer rate associated with this steady state process is most closely 1)-2,02 btu/s from the liquid to the surroundings 2)-3.98 btu/s from the surroundings to the liquid. 3)-4.96 btu/s from the surroundings to the liquid. 4)-1.04 btu/s from the liquid to the surroundings.