Consider a conical surface (open) of height h and radius of the base r uniformly charged with surface charge density \sigma . choose the axes so that the vertex of the cone is at the origin and its axis of symmetry coincides with the axis oz . calculate the work of the electrostatic force exerted by the cone on a point charge q when that charge is taken from the vertex of the cone to infinity

An object with initial temperature 130 ∘ f is submerged in large tank of water whose temperature is 50 ∘ f . find a formula for f ( t ) , the temperature of the object after t minutes, if the cooling constant is k = − 0.2 . remember newton's law of cooling (the rate of change of temperature with respect to time is equal to k times the difference between the temperature of the object and the surrounding temperature) ! : )