Current can be the flow of negative or positive charges or both. The conventional current direction of flow is the direction of flow of the positive charges, but the positive charges are immobile. Electrons carry the negative charge and in the direction opposite to that of electric or conventional current. For instance, if two metal plates or any other conductors are connected together by a wire e.g. copper wire, electrons flow from the conductor with higher potential toward the conductor with lower potential due to the potential difference between them. The electrons flowing between the two is referred as electricity and decreases with the decrease in the electrical potential. Therefore, it is necessary to maintain the electrical potential difference by using devices like the battery, solar cells, or electrical generators and is connected to loads like motors, light bulbs, heaters etc. Since these devices are loads, they slow down the flow of electrons due to the electrical resistance they offer.. Two main types of current are DC and AC....

It is necessary to control current flowing in a circuit either by controlling the amount of voltage applied or the resistance in the circuit. This is done to avoid the undesirable results like damaging electrical components or valuables at home if for instance the optimal operating conditions are exceeded. Ammeter is used to measure the electrical current flowing through a circuit while voltmeter measures the electrical potential difference. Ammeter is placed in series and voltmeter in parallel with other components in the circuit. The ammeter will only measure the current in the branch it is placed but not current flowing in other branches of the circuit. Ammeters have relatively low resistance while voltmeters have high resistance. Power sources like a battery, generators are needed to keep current flowing in a circuit (Voltage-force which pushes the electrons) and also the circuit must be complete for the electrons to return to their source implying that conductors are necessary for current to flow. Insulators like glass or plastic are needed to avoid current leakage or short circuiting which may result to cut off supply of power to various electrical devices or even damage them. The relationship between current, voltage and resistance in a circuit is clearly defined by Ohm’s law which states that “electrical current is proportional to the voltage and inversely proportional to the resistance between any two points on a conductor provided the temperature of the conductor does not change” (James, Jack and Noble). I=V/R where: I=current (Amperes), V=Voltage(volts), R=Resistance (Ohms).Therefore when current increases, voltage in the circuit
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