)(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.

Acalorimeter uses the principle that thermal energy flows from hotter material to colder material until both reach the same

Which statement best describes the direction of the buoyant force on any object? a. opposite the force of gravity b. in the same direction as the weight c. in the direction of motion of the object d. opposite the direction of motion of the object

69. air frictionthe velocity of the satellitea. decreases b. increases c. sometimes increases sometimedecreases d. no effect at all70. the unit of gravitational potential energy isa. jouté b. watt c. newtond. pascal71. which of the following is not influenced by a magneta. cobalt b. copper c. irond. nickel72. one joule of work done in one second by unit positive chargea.1 watt b.1 volt c.1 js d. none73. the most deviated colour of light after passing through a prisea. violet b. red c. green d. yellow4. a coin is placed below a beaker fill with water upto 12 cm isdisplaced by water isa. 9cm b.6cmс.3cmd.7cm