$2\mathrm{.}3$ The power source in a particular welding setup generates $4000$ W that can be transferred to the work surface with a heat transfer factor $=0\mathrm{.}8.$ The metal to be welded is low carbon steel, whose melting temperature, from Table $29\mathrm{.}2,$ is $1760$ K $.$ The melting factor in the operation is $0\mathrm{.}5.$ A continuous fillet weld is to be made with a crosssectional area $=20m{m}^2.$ Determine the travel speed at which the welding operation can be accomplished.