Higher Physics Lab Heat



Exp-1 To determine the heat capacity of the calorimeter.
Exp-2 To study the thermal conductivity of copper and aluminum in a constant temperature gradient.
Exp-3 To determine the electrical conductivity of aluminum and copper by plotting a current-voltage characteristic curve.
Exp-4 To verify the Wiedmann-Franz law and find out the Lorenz number.

  • Safety tested high current power supply.
  • Multipurpose data logger.
  • Sample rod (Copper & Aluminum).
  • Microvoltmeter.
  • Heat transportation.
  • Thermal conductivity.
  • Electrical conductivity.
  • Phonon.
  • Temperature gradient.
  • Wiedmann-Franz law
  • Lorenz number.

Principle and Working:
The heat conduction occurs due to the temperature difference between different locations of a body. In this setup a one-dimensional temperature gradient along a copper and aluminum rod is investigated. The quantity of heat dQ transported with time dt is a function of the cross-sectional area A and the temperature gradient dT/dx perpendicular to the surface is defined as:

dQ/dt = -λ A (dT/dx)

λ is the thermal conductivity of the substance.
The electrical conductivity of a metal (Copper & Aluminum) is determined by the resistance R of the rod and its geometric dimensions (l=0.315 m, A = 4.91 x10-4 m2)
σ = l/(A.R)

At room temperature T the conduction electrons in metal have a much greater mean free path than the phonons. For this reason heat conduction in metal is primarily due to the electrons. The relationship between the thermal conductivity λ and the electrical conductivity σ is established by the Wiedmann-Franz law:
λ/σ = L T
Where L is Lorenz number.


Cat. No. Item Name Qty.
CD549 Conductivity rod Cu 1
CD550 Conductivity rod Al 1
CD554 Calorimeter Vessel 1
CD553 Calorimeter Vessel with rod holder 1
SW979 Laboratory jack 1
R8213 Digital weighing balance 1
IH Immersion heater 1
  Temperature sensor 3
  Data Logging Interface 1
SV190 Three finger clamp 3
  Support base (Cat no. SH319+SH317) 1+1
  Support rod (Cat no. SH323+SH316) 1+1
SW092 Bosshead 5
SE1003 Power supply 20Amp 1
SR010 Microvoltmeter 1
LP18 Connecting lead 4
SC228 Glass beaker 1

* Additionally Required
Computer not supplied with this setup.