Many kinds of analysis in the physical sciences are helped by identifying quantities that are constant. It is usual to begin by assuming that the battery is ideal when analyzing these circuits l. Is any quantity (related to the battery) constant in circuits 7 & 8? If so, what quantity? (Hint; you should be able to use a DMM to measure it.)

As, there are different physical quantities which are required to be measured in a more proper way to define the circuits properties. As, there is current,I which is the more directed flow of electrons inside the circuit.Along, with which the voltage,V or in other words the potential difference inside the circuit is also taken under consideration.And most importantly the resistance's,R value inside the circuit defines the parameters inside the circuit. All of these values are then determined or analyzed with the help of the digital multi-meter or simply the DMM.