Atube bank uses an aligned arrangement of 10-mm-diameter tubes with st = sl = 20 mm. there are 10 rows of tubes with 50 tubes in each row. consider an application for which cold water flows through the tubes, maintaining the outer surface temperature at 27°c, while flue gases at 427°c and a velocity of 5 m/s are in cross flow over the tubes. the properties of the flue gas may be approximated as those of atmospheric air at 427°c. what is the total rate of heat transfer per unit length of the tubes in the bank?

At time t=0, a particle is located at the point (3,6,9). it travels in a straight line to the point (5,2,7), has speed 8 at (3,6,9) and constant acceleration 2i−4j−2k. find an equation for the position vector of the particle.

While studying chemical reactions and conservation of matter, sarah's class conducted a variety of experiments. sarah and her lab partner found the mass of a wax candle and placed the candle in a flask. the students lit the candle and let it burn to completion. all that was left was wax and charred candle wick. per their teacher's instructions, the students found the mass of the products. their data can be seen in the data table. formulate a hypothesis the students could test to explain why the experiment did not support the law of conservation of matter. a) the students could repeat the experiment using different candles; there might have been a flaw in the candle. b) the experiment should be repeatable. the students should run several trials and then take an average of the after mass in each trial. c) the students should have someone in the class check their measurement skills as they repeat the experiment. they may have made an error using the balance. d) the students should burn the candle in a container that has some type of lid so that any gas that is a product of the reaction can be contained and massed. submit

J. j. thomson’s experiment disproved the theory that an atom