Duff states that equal masses of all substances have equal changes in internal energy when they have equal changes in temperature. javan states that the change in internal energy is equal to a constant times the change in temperature for every δt, no matter how large or how small δt is, but that the constant is different for different substances. which one, if either, is correct

What are igneous intrusions and extrusions

The coefficient of friction is a number that represents the resistance to sliding between two in contact with one another.

Ahair dryer is basically a duct in which a few layers of electric resistors are placed. a small fan pulls the air in and forces it through the resistors where it is heated. air enters a 1200 w hair dryer at 100 kpa and 22°c and leaves at 47°c. the cross-sectional area of the hair dryer at the exit is 60 cm2. neglecting the power consumed by the fan and the heat losses through the walls of the hair dryer, determine (a) the volume flow rate of air at the inlet and (b) the velocity of the air at the exit.