Joule’s Experiment as a Probe into Micro-World

Joule ́s experiment has both the historical and pedagogical importance in the building of the bridge between macro and micro-world. Dissipative forces and their work as a transformation of the macroscopic mechanical energy into the energy of thermal motion are decisive in the study of mechanical phenomena of real world. In this work we introduce the ISES Joule ́s remote experiment that qualitatively and quantitatively describes the transformation of macroscopic kinetic energy into heat and shows the quantities, active in the transformation. The remote experiment represents a new generation of ISES remote experiments, equipped with a module, providing diagnostic information on remote experiments, both for the client and the provider.


I. INTRODUCTION
The Joule´s experiment played the decisive role in the insight into micro-world of the 19th Century and proved the equivalence of the concept of energy for both microand micro-world. This is the reason to build the Joules´ experiment for contemporary teaching, as insight into micro-world is difficult point for the teacher to explain. The remote experiment (RE), though relying on the original concept, uses modern experimental parts of the standard setup of ISES RE [1], [2]. In Fig. 1 is the arrangement of the laboratory experiment with its constituent parts.

A. Principle
The Joule´s experiment, which dates back to 1840, was originally designed as a system of rotating paddles in a thermally isolated vessel filled with water, arranged so that they can revolve. The rotation was due to the system of two weights moving downwards, so that the transformation of the potential energy of the gravity of the weights to the kinetic energy of the rotating paddles takes place with a successive transformation into heat.

B. Laboratory Joule´s experiment
The arrangement of the Joule´s laboratory experiment is in Fig. 1, based on the components of Phywe. The adjustable friction force by the weight (8) and measured by the dynamometer (1) is exerted by the plastic belt, which is wound on the rotating cylindrical metallic body (3). The generated heat is increasing the temperature of the metallic body, measured by the ISES thermometer (5). The driving force for the rotation of the cylindrical body is exerted by the motor (8) (DC 12V) driven and controlled by a DC source.

C. Data collection
The data collection system is based on the Internet School Experimental System (ISES) [1] where the ISES modules for the temperature measurements and the optical ISES gate for the No of revolutions elapsed are used. In Fig. 2 are samples of the experimental data. In the upper SHORT PAPER JOULE´S EXPERIMENT AS A PROBE INTO MICRO WORLD part is the record of the signal from the optical gate for the measurement of the number of revolutions during the experiment serving for the calculation of the covered path. Beneath is the recorded signal from the ISES thermometer, measuring the increase of the temperature on the time during the experiment (3-5°C).

A. Construction of remote experiment
The transformation of the laboratory experiment ( Fig.1) to its remote counterpart (see Fig. 3) was accomplished using the modules of the ISES thermometer, the ISES optical gate, and the ISES relay for the supply of the driving motor. The ISES RE is based on the state machine principle with the .pds controlling file, and the controlling program in Javascript, compiled using the Easy Remote ISES (ER-ISES) environment [3] [4].

B. Two types of diagnosti systems
The crucial drawback of the existing REs is the lack of feedback of their proper functioning. The clients are then disgusted and are repelled from the regular use of REs as a result. In our current Measureserver two types for the diagnosis of the RE were built in ([5]).
One system (Fig. 4) signals by the "traffic lights" the available experiment ((a) green light), occupation of the experiment (temporary or permanent) ((b) orange light) and out of order experiment -not available for the service (red light (c)).
The second, more sophisticated diagnostic system, watches for the proper functioning of all the components of the RE. In Fig. 5 are displayed the continuous reports in regular time intervals on the state of the physical hardware. By the green color are denoted the correct set up and functions and two typical fault events, indicated by the red color. If the range or the sensitivity of any modules changes (see the event A in Fig. 5, red color), or if any module is disconnected (see the event B in Fig. 5, the red color), the corresponding report occurs and e-m message is sent to the experiment owner and to REMLABNET as a service request.
At the beginning of the remote experiment programming the ISES components and modules of the experiment are collected in the reference list with their sensitivity or ranges (see more details in [5]).

IV. RESULTS AND EVALUATION
Let us present a piece of the theory of the Joules´ experiment. The friction force between the belt and the cylindrical metallic body surface is equal to the difference between the force F 2 measured by the force meter and the weight of the used weight F 1 . (1) The work of friction forces is equal to the friction force multiplied by the path covered by the rotating body (2) Where r is the cylinder radius and n is the number of revolutions. This work is compared with the heat absorbed by the rotating body, where m is the mass of the body and "T is its temperature increase the specific heat c that may be determined and compared with that from the tables (4) iJOE -Volume 12, Issue 6, 2016

V. RESULTS AND EVALUATION
The presented remote experiment "Joule´s experiment" constitutes an important tool for teaching physics in general and the teaching of micro-world in particular. The conclusions may be formulated: The ISES framework both on the level of physical hardware and ISES remote experiments software (ER-ISES) is suitable for the easy construction of a rather wide range of remote experiments, including Joules´ remote experiment 1. The Joules´ experiment was built and optimized as to heat transport, heat losses and running parameters of the experiment and gives reliable results. 2. The new series of remote experiments with diagnostics was initiated, sensing and reporting both the availability of the remote experiment and its functioning.
The remote experiment "Joule´s experiment" was connected and made available via our RLMS REMLABNET network (http://remlabnet.eu ) and also to the EU FP7 portal Go-lab (http://www.golabz.eu)