The drag force, fd, imposed by the surrounding air on a vehicle moving with velocity v is given by fd = cdaρv 2/2 where cd is a constant called the drag coefficient, a is the projected frontal area of the vehicle, and ρ is the air density. an automobile is moving at v = 80 kilometers per hour with cd = 0.28, a = 2.3 m2, and ρ = 1.2 kg/m3.

You have a resistor and a capacitor of unknown values. first, you charge the capacitor and discharge it through the resistor. by monitoring the capacitor voltage on an oscilloscope, you see that the voltage decays to half its initial value in 2.70 miss . you then use the resistor and capacitor to make a low-pass filter. what is the crossover frequency fc?

Nitrogen (n2) undergoes an internally reversible process from 6 bar, 247°c during which pν1.2 = constant. the initial volume is 0.1 m3 and the work for the process is 121.14 kj. assuming ideal gas behavior, and neglecting kinetic and potential energy effects, determine heat transfer, in kj, and the entropy change, in kj/s. show the process on a t-s diagram.

The two metal spheres in the figure are connected by a metal wire with w switch in the middle. initially the switch is open. sphere 1, with the larger radius, i'd given a positive charge. sphere 2, with the smaller radius, is neutral. then the switch is closed. afterward, sphere 1 has charge q1, is at potential v1 and the electric field strength at its surface is e1. the values for sphere 2 are q2, v2, and e2. a. is v1 < ,> , or = to v2? explain. b. is q2 < , > , or = explain? c. is e1 < ,> ,or = to e2? explain?