Question

describe an experiment with a neat labelled circuit diagram to Verify Ohm's law​

Answer 1

${\mathfrak{\green{\underline{\underline{Question:-}}}}}$

Describe an experiment with a neat labelled circuit diagram to Verify Ohm's law.

${\mathfrak{\green{\underline{\underline{Solution:-}}}}}$

${\bf{\red{\underline{\underline{Ohm's\;Law:-}}}}}$

Ohm's law states that the current flowing through a device is directly proportional to the potential difference applied to the device. The constant of proportion is called the resistance of the device when it is formulated mathematically as:

$\bf{\red{V=IR}}$

Where V is the voltage across an element of the circuit in volts, I is the current passing through the element in amps and R is the resistance of the element in ohms. Given any two of these quantity ohm's law can be used to solve for the third.

${\bf{\red{\underline{\underline{Corresponding\;SI\;units:-}}}}}$

$\bf{Volt(V)=ohm(\Omega)\;.ampere(A)}$

Ohm's law can be written as:

★ ${\boxed{\boxed{\sf{\red{I=\dfrac{V}{R}}}}}}$

★ ${\boxed{\boxed{\sf{\red{R=\dfrac{V}{I}}}}}}$

${\bf{\red{\underline{\underline{Electrical\;circuit\;for\;Verification\;of\;Ohm's\;law:-}}}}}$

To verify Ohm's law, the following circuit is used which is in attachment file.

In the attachment file the diagram is of the circuit used in the lab for verification of ohm's law.

In a circuit: B is the battery to supply the current to the circuit, Rh is rheostat to control the current in a circuit, K is key to connect or break the circuit, A is ammeter to measure the current in a circuit, V is the voltmeter to measure the potential difference across the resistance wire to provide resistance.

Points to note:

1). The Rheostat Rh, the key K, ammeter A, and the resistance wire R are connected in series with battery B.

2). The positive side of the ammeter should be towards the positive terminal of the battery.

3). The voltmeter V is connected parallel to the resistance wire.

4). The positive side of the voltmeter should be towards the positive side of the battery.

${\bf{\red{\underline{\underline{Procedure\;for\;the\;Verification\;of\;Ohm's\;law:-}}}}}$

1). Key K is closed and the Rheostat is adjusted so as to get minimum reading in the ammeter and voltmeter.

2). The rheostat is then gradually moved so that the current in the circuit increases.

3). Each time the rheostat is moved, the reading of the current (I) flowing in the circuit and potential difference across the resistance is measured by noting the readings of the ammeter and voltmeter.

4). Thus, different sets of values are obtained in a table and the ratio of the current (I) and the potential difference (V) is calculated for each set of values.

5). It is noted that the ratio of the current and potential difference is same or almost the same for each set of values in the table.

6). Now a graph is plotted for V, against I, in which the potential difference V is taken on the y axis and the current is taken on the x axis.

7). The graph obtained is a straight line and the slope of this line is the value of the ratio of V verses I.

Thus, it is proved that the ratio of V verses I is a constant value, that is, $\sf{\dfrac{V}{I}=constant=R.}$ Thus, ohm's law is verified.