Adiabatic and isothermal processes are difficult for beginning physics students to understand. PASCO's Adiabatic Gas Law apparatus provides the ideal dem­on­stra­tion.

A Versatile Lab Tool

  • Compare the final pressure and temperature: values predicted by the Adiabatic Gas Law.
  • Measure the work done on the gas: compare it to the change in internal energy and the theoretical work performed.
  • Determine gamma: the ratio of specific heats for the gas (Cp/Cv).
  • Use monatomic, diatomic and polyatomic gases: determine the effects of molecular structure on gamma.
  • Investigate isothermal com­pres­sion and expansion.


PASCO's Adiabatic Gas Law can be used with the ScienceWorkshop Interface. The computer functions as a 3-channel storage os­cil­lo­scope, plotting graphs of pressure, temper­a­ture and volume as well as integrating the area under a pressure versus volume curve to determine the work done on the gas.

Special Features

  • Volume Transducer: A linear po­ten­tial divider is mounted on the side of the piston. A 5-Volt source from the comput­er is applied across the potentiometer element. The voltage from the com­mu­ta­tor brush on the cylinder is used to indicate the position of the piston and the volume of the confined gas.
  • Pressure Sensor: A solid-state, piezoresistive device that forms part of a bridge circuit is mounted at the base of the cylinder.
  • Temperature Sensor: Mounted in the cylinder on the top of the base. The active element is fine nickel wire with a high surface-to-mass ratio. The wire's temperature changes rapidly as the gas compresses or expands.


  • Adiabatic Gas Law Apparatus
  • Instruction manual, experiment guide and the fully documented experiment, "Measurement of Work to Compress Gases Adiabatically" (sample data included).
  • Signal Cables 3.5 mm plug to 5-pin DIN
  • Power Adapter 9V DC @ 1A
  • Buying Guide


    Gases: argon (monatomic), air or nitrogen (diatomic), carbon dioxide (triatomic).

    Required - One of the following

    Of current PASCO interfaces only the 850 Universal Interface has the 3 required analog ports.  

    However, a 550 Universal Interface could be used plugging into the two analog ports with an analog adapter (PS-2158) in one of the PASPORT ports to give three analog ports.

    The discontinued ScienceWorkshop 500 and 750 interfaces can also be used. 

    Interface Required

    This product requires an 850 Universal Interface for use.

    Have specific questions or need more information about the 850? Contact Teacher and Technical Support.  We're here to help!

    Software Required

    This product requires or recommends PASCO Capstone for data collection and analysis.