Water is heated at a rate of 10 kg/s from a temperature of 15°c to 35°c by passing it through five identical tubes, each 5.0 cm in diameter, whose surface temperature is 60.0°c. estimate (a) the steady rate of heat transfer and (b) the length of tubes needed to accomplish this task.

Two point charges are separated by a certain distance. how does the strength of the electric field produced by the first charge, at the position of the second charge, change if the second charge is doubled? a. the field does not change b. the field strength decreases by half. c. the field strength doubles d. the field strength quadruples