The size of the picture of a nanparticle is measured to be 5.2 cm by a ruler. if the scale bar size is 3 cm and is labeled 40 nm, find the actual size of the particle.

In the circuit, the switch s has been open for a long time and r = 125 kohm. it is then suddenly closed. (a) determine the time constant before the switch is closed. s (b) determine the time constant after the switch is closed. _ s (c) let the switch be closed at t = 0. find the current in the switch as a function of time. (use t for time. express your answer in milliamps and seconds.) i(t) =_