A potentiometer wire of length 1m and resistance 2Ω is connected in series with a variable resistance and 2V accumulator of negligible resistance. What must be the variable resistance so that the fall of electric potential across the wire is 1mV/cm?

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.

If you visited mount shasta city (elevation 900 m [3000 ft.]) and found the outside air temperature to be 27°c (81°f), what would be the air temperature at the summit of mount shasta (elevation 4200 m [14,000 ft.]) at that moment-assuming that the temperature conditions with altitude change at an average, or normal, lapse rate?

A47 kg person in a rollercoaster moving through the bottom of a curved track of radius 47.7 m feels a normal force of 895 n. what is the net centripedal force acting on the person