I experience a lot of difficulty in explaining the waveforms of an RC differentiation circuit. Consider a battery of voltage V connected through a switch to a capacitor C and one end A of a resistor R. The other free end B of the resistor R is connected to the negative terminal of the battery. When the switch is closed, a sharp rise in voltage (A with respect to B) is observed across the resistor. Most of the text books I referred to state that since "the voltage across the capacitor cannot change instantaneously provided the current remains finite" one observes the sharp rise in voltage across the resistor. Refer "Pulse, Digital and Switching Waveforms" by Jacob Millman and Herbert Taub. When students ask me for an explanation of what is happening across the capacitor involving potentials and charges, I experience difficulties. Can someone provide a reasonable explanation using potentials, electric fields and charge movement or one at a more microscopic level ? Thanks Sridhar Chitta Assoc. Prof Dept of Instrumentation and Control Engg Vignan Institute of Technology and Science Village Deshmukhi Nalgonda Distt Pin code: 508284 near Hyderabad Andhra Pradesh India website: www.vignanits.ac.in