Rahul Khora's class 12 physics project is on the meter bridge. The meter bridge is a device used to measure unknown resistances based on the Wheatstone bridge principle of balancing a circuit so that no current flows through the galvanometer. It consists of a 1 meter long wire with resistances R and S connected at gaps, and a jockey that slides along the wire to find the null point and calculate the unknown resistance. The meter bridge procedure involves setting up the circuit with a known resistance R, finding the null point where the galvanometer shows no deflection, and using the position to calculate the unknown resistance.

1. PHYSICS 2023-24
PROJECT
NAME – RAHUL KHORA
CLASS – 12TH
TOPIC – METER BRIDGE

2. TABLE OF CONTENTS :-
•METER BRIDGE
•WHAT IS METER BRIDGE ?
• THE PRINCIPLE OF METER BRIDGE
•CONSTRUCTION OF A METER BRIDGE
•FINDING UNKNOWN RESISTANCE USING METER BRIDGE
•THINGS TO REMEMBER
•BIBLIOGRAPHY

3. • Meter Bridge: A meter bridge, also known as a slide wire bridge,
is a device that works on the Wheatstone bridge idea. A metre
bridge is used to find the unknown resistance of a conductor. In
Physics, while theory forms the basis of our knowledge, practicals
form our understanding. What is this device? This is a meter
bridge! It consists of a wire of one meter, which is why it is called a
‘meter bridge’. It is used to measure the resistance of wires, coils or
any other material. Please read on to learn about the meter
bridge formula, meter bridge diagram, and more.

4. WHAT IS METER BRIDGE ?
• A Meter Bridge is an electrical apparatus using which we can measure the
value of unknown resistance. It is made using a metre long wire of uniform
cross-section. This wire is either nichrome or manganin or constantan because
they offer high resistance and low-temperature coefficient of resistance. A
meter bridge or Slide wire bridge is designed from a Wheatstone bridge. It is
the most basic and functional application of a Wheatstone bridge.

5. •A Meter Bridge works on the principle of a Wheatstone
bridge. A Wheatstone bridge is based on the principle of
null deflection, i.e. When the ratio of resistances in the two
arms is equal, no current will flow through the middle arm
of the circuit. Consider the diagram of the Wheatstone
bridge as shown below. It consists of four resistances P,Q,R
and S with a battery of EMF .
THE PRINCIPLE OF METER BRIDGE

6. • In the balanced condition, no current flows
through the galvanometer, and terminals, B and D
are at the same potential. This condition arises
when, P = R
Q S

7. CONSTRUCTION OF A METER BRIDGE
• A meter bridge has a 1m long wire of uniform cross-section area,
which is stretched tight.
• Between two metal strips that are bent at right angles, this wire is
then carefully clamped, as shown in the diagram below:
• Within the gap between the metal stripes, resistances are
connected. In the first gap, R, a resistance box, and in the second
gap, a small resistor wire S is connected.
• The endpoints within which the wire is clamped are connected to a
key through the cell.

8. • A galvanometer is connected to the metallic right in the middle of
the two gaps.
• A jockey is connected at the other end of the galvanometer (Here,
a jockey is a metal rod with a knife-like edge at one end that
slides over the potentiometer wire to make an electrical
connection). The jockey is slid over the meter bridge wire till the
galvanometer shows zero deflection.

9. FINDING UNKNOWN RESISTANCE USING METER
BRIDGE
• To find the unknown resistance using meter bridge, given below step-by-step procedure must be followed:
• Gather the instruments and get ready associations as demonstrated in the above figure.
• Take some appropriate sort of obstruction ‘R’ from the opposition box.
• Contact jockey at point A; look that there exists an avoidance in the galvanometeron one of the sides, at that
point contact the rider on point C of wire, at that point the diversion in the galvanometermust be on another
side.
• Discover the situation of the invalid point having redirection in the galvanometerthat gets zero.
• Proceed with the above strategy for various estimations of the ‘R’. Note probably around 5 readings.
• Consider where the galvanometershows a 0 avoidance; this is known as the equilibriumpoint.
• Presently, Measure the length of a given wire by the utilization of standard scale and range of the wire by the
usage of a screw check, (Take in any event five readings).
• Compute Mean Resistance of Single Unknown Resistance = Total Sum of protections of Unknown opposition
from the over five readings)/5.

10. THINGS TO REMEMBER !!!
• Meter Bridge is used to find the unknown resistance of a conductor as that of
in a wheatstone bridge.
• A Meter connect is a sort of electrical circuit utilized in estimating an electrical
obstruction. Which is obscure by adjusting its two legs of the scaffold circuit,
where one of the legs incorporates an obscure segment.
• The flow of electric charge is known as electric current. It is calculated as a
charge flow rate. It refers to the volume of charge flowing over time.
• Amperes is a unit of measurement (A).
• Samuel Hunter Christie made this instrument in the year 1833 and was
improved and rearranged by Sir Charles Wheatstone in the year 1843.

11. BIBLIOGRAPHY
• Internet
• CBSE text book
• www.topper.com
• www.studyrankers.com
• www.physicsadda.com