Thermal And Electrical Conductivity With Digital Sensor

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.
So 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 m 2 )
σ = R.A/l
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.

Features:

• Digital Weighing scales with maximum capacity of 5 kg or more.
• PT-100 based digital thermometer with accuracy of 0.1 degree Celsius.
• Test samples Like Copper and Aluminum with insulated cover.
• Free data analyzing software.
• DC Regulated power supply with safety sockets and dual temperature controlled exhaust fan.
• Water heater with built-in steam generator.

Objectives:

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

Technical Data:

Digital timer & photogate:

• Conductivity Rod : Cu/Al, size 420 x25.4mm (L x Φ),4mm current socket, 2 temperature point
• Digital Temperature Sensor : Pt-100, Range -50 to +199.9 C, Resolution thermometer 0.1 C, Accuracy ± 0.2 C ± 1, digit, Battery 9V
• Digital micro : Range 19.999 mV – 1000 V, accuracy 0.5% rgd + 3 dgt, resolution 0.001mV to 0.1mV
• Power supply : Output Voltage 0-30V, Resolution 0.1V, Output Current 0-20 Amp, Resolution 0.1 Amp, Primary fuse 8 A

Scope of Delivery:

• 1 Conductivity Cu & Al rod
• 1 Lower Calorimeter Vessel
• 1 Calorimeter Vessel with heater
• 1 Laboratory jack
• 1 Digital weighing balance
• 2 Three finger clamp
• 1 Support base & Support rod
• 3 Digital temperature thermometer
• 1 Power supply 0-30V, 20amp
• 1 Micro voltmeter
• 2 Connecting lead(Red & Black)
• 1 Accessories: Glass beaker (500 ml)
• 2 Heat conductive paste
• 1 Laboratory gloves
• 1 Vernier calliper
• 1 Plastic beaker (2000ml)
• 2 Bosshead