)(si units) a shielded metal arc-welding operation is performed on low-carbon steel plates at a voltage = 25 volts and current = 150 amps. the heat transfer factor = 0.90, and the melting factor = 0.75. the melting temperature of low-carbon steel = 1487°c, and the unit melting energy can be determined by the methods of the previous chapter. using si units, determine the (a) rate of heat generation at the weld and (b) volume rate of metal welded.

Which statement is true? a) the work done to lift an object 6 meters is greater than the gravitational potential energy it gains. b) the work required to push an object is less than the work required to pull an object the same distance. c) the work required to raise an object to a height is equal to the gravitational potential energy the object gains. d) the work done against gravity to lift an object straight up is greater than the work required to roll it up a ramp.