Archive for the ‘Applied Physics for Engineers’ Category
Kirchoof’s Current Law
OBJECT:
- To verify Kirchoff’s Current Law (KCL)
- To verify Current Divider Rule (CDR)
EQUIPMENT:
- DC power supply (0-30V)
- DMM
- Resistors of different values
- Connecting wires
- Digital Experiment Board
THEORY:
KCL states that:
“The sum of currents flowing into a point in a circuit is equal to the sum of the currents flowing out of that same point”
CIRCUIT DIAGRAM:
Resistivity and Conductivity of Eureka wire
Objective:-
To determine the resistivity and conductivity of Eureka wire.
Apparatus:-
- Power supply (0 – 300V)
- Ammeter
- Voltmeter
- Eureka wire
- Screw gauge
- Meter rod
- Connecting wires
Theory:-
Resistivity or specific resistance of a material is defined as the resistance of a unit volume of the material. If ‘R’ is the resistance, ‘A’ is the area of cross section, ‘L’ is the length of a wire and a current ‘I’ is passing through its area ‘A’, then:
R α L/A
R = Constant × L/A
Constant = R ×A/L
This constant is called Resistivity of the material ‘ρ’. The inverse of resistivity is called Conductivity ‘σ’ of the material given by:
ρ = R ×A/L Ω-m
σ = 1/ ρ (Ω -m)-1