How do you find the internal resistance and EMF of a cell?

The current flowing through the circuit is measured with a suitable milliammeter and the potential difference across the variable resistor is measured with a voltmeter for a range of resistance values. Plot a graph of these results and determine the e.m.f. and the internal resistance directly from the graph.

How do you find the EMF of a cell?

The EMF of the cell can be determined by measuring the voltage across the cell using a voltmeter and the current in the circuit using an ammeter for various resistances.

What is internal resistance of a cell write factors on which internal resistance of a cell depends?

Thus, the internal resistance of a cell depends on the factors like distance between the electrodes, the temperature, the effective area of the electrodes and the concentration of the solution.

What do you mean by internal resistance?

Internal Resistance is the resistance which is present within the battery that resists the current flow when connected to a circuit. Thus, it causes a voltage drop when current flows through it. It is the resistance provided by the electrolyte and electrodes which is present in a cell.

What is the value of internal resistance of a cell?

We would normally expect an AA cell to have an EMF of about 1.5 V and an internal resistance of about 1 Ω.

What is the EMF of a cell?

The electromotive force of a cell or EMF of a cell is the maximum potential difference between two electrodes of a cell. It can also be defined as the net voltage between the oxidation and reduction half-reactions. The EMF of a cell is mainly used to determine whether an electrochemical cell is galvanic or not.

How to find the EMF(E) and internal resistance(R) of a cell apparatus?

Experiment to find the emf (E) and the internal resistance (r) of a cell Apparatus : 1.5V (approx) cell, Resistance box, Push switch, Digital Ammeter (0-1A). Method Check the scale on the digital ammeter by comparing to other ammeters. Set R at 10 Ohms. Reduce in steps of 1 Ohm, recording resistance and current.

How to write an effective introduction to a lab report?

An effective introduction to a lab report typically performs the following tasks, generally in the order presented: 1. it establishes the learning context for the lab by: a. saying what the lab is about, that is, what scientific concept (theory, principle, procedure, etc.)Ý the researcher is supposed to be learning about by doing the lab; and.

What is the purpose of writing a lab report?

The main purpose of writing a lab report, of course, is not to contribute to the knowledge of the field; but to provide you the opportunity for learning. That’s why it’s important to begin the lab by establishing that learning context.

How do you calculate the internal resistance of a cell?

The internal resistance of a cell is simply the resistance from one terminal of the cell to the other. since V = IR then E = I (R+r) so E/I = R + r