Introduction

To determine Mechanical Equivalent of Heat, J, by Callender and Barne’s Method.

Callendar and Barn’s apparatus consists of Nichrome resistance wire in the form of the coil placed centrally along the axis of a narrow glass tube. This wire serves as heater as well as stirrer. The ends of wire are connected to metal tubes provided at the ends of glass tube. Continuous flow of water is maintained (using a constant level bath) through the tube and the temperatures of inlet and outlet are measured by two thermometers T1 and T2.