النشر العلمي

  • Measurements of Heat Capacity from Lattice Vibrations of Solids by Using Debye Model

Heat capacity is a measurable physical quantity that
characterizes the ability of a body to store heat as it
temperature changes, it is defined as the amount of
heat that changes the temperature of the body at the
given conditions. The objectives of this work are
the study of total energy of the phonon at
temperature T, heat capacity of solids and Debye
heat capacity model. The solid sample of metal
such as (Al, Cu and Fe) of weight 0.25 Kg in an
electric heater inserted completely inside a deep
hole into the metal and a thermometer inside
another deep hole. Both heater and thermometer
must make good thermal contact with the sample.
The metal was by an insulator. The theory of
specific heat in solids shows that specific heat
capacity for a material normally increases with
temperature, due to the change in substance
structure, more precisely, it depends on how many
degrees of freedom are available in the substance
particles, where a degree of freedom is a form of
energy in which is stored in the object. Results
show that, the average heat capacity of samples, at
different temperatures from are
(Al=982.1140 Cu =4740.3262
and Fe =241.9965 ), take the uncertainties
for the different measurements showed that
accuracy depended very little on the sample. All
though Debye heat capacity model is the best
theoretical model to study the heat capacity in
solids, modern research has revealed somediscrepancy in the model at low temperatures and
that Debye´s temperature is not a constant, but
varies with temperature.

published in discrepancy in the model at low temperatures and that Debye´s temperature is not a constant, but varies with temperature.

  • DETERMINATION OF ENERGY GAP OF ZINC OXIDE (ZNO) BY ELECTRIC METHOD OF DIFFERENT TEMPERATURE

In this study, put a sample of zinc oxide in electric circuit, circuit consists of a power supply, ammeter and
voltmeter. Fifty (50) readings for voltage(mV ) and current(mA ) are taken. A graph relating the current to the voltage is
drawn for zinc oxide sample. It was found that for zinc oxide the current increases abruptly at about (0.5 and 4.1) Volt.
The value of the energy gap of zinc oxide by using this electrical method (3.59 to 2.89) eV . This method is effective in
the calculation of the energy gap for some semiconductors and solid materials. Exposure of these samples to the heat
increases the current which agrees with the fact that heat increases electron velocity. The exposures of samples to the high
temperature decrease the energy gap which agrees with some works.

published in International Journal of Physics and Research (IJPR)

  • THE EFFECT OF SPEED AND POTENTIAL ON TIME, MASS AND ENERGY ON THE BASIS NEWTON AND RELATIVITY PREDICTION

The nature of time, mass, and energy, and the effect of speed and potential field on them was experimentally tested.
These experiments show that the time, mass, and energy are affected by both speed and potential.
Newtonian mechanics shows that only energy is affected by speed and potential. Thus it is in direct conflict
with experiments that shows the effect of speed and potential on time and mass. However special relativity shows
the effect of speed on time, mass, and energy but does not recognize the effect of potential on them.
But generalized special relativity shows that time, mass, and energy are affected by velocity as well as field
potentials. Fortunately the theoretical relations agree with the empirical ones.

published in INTERNATIONALJOURNALOFENGINEERING SCIENCES&MANAGEMENT

  • Deriving of the Length Contraction in the Presence of the Gravitation in General Special Relativity by Using a Light Clock

Generalized special relativity is one of the most promising models that is found to cure many defects
of special relativity. These defects include un capability of explaining gravitational red shift and satisfaction of
the Newtonian limit.
Despite these successes generalized special relativity suffers from noticeable setbacks. First of all its way of
derivation make it restricted to weak fields only. Although recent derivation make it applicable to fields other
than the weak and gravitational field, but this derivation needs to be strengthen.
In this work a light clock is used to derive a useful expression for time, length, in General special relativity.
These expressions are typical to that derived before by using curved space. Time, but they are not restricted
gravitational and weak fields. The expressions for time, length holds for all fields.

published in IOSR Journal of Applied Physics (IOSR-JAP)

  • Determination of energy gap copper oxide by four probe methods

In this study, on a four-probe, I put a sample of copper oxide, size (10x15x3mm ) 3
. Was used
Then, electric current is passed at magnitude 8mA at different temperatures in the range (29 -150 ) 0 0 . And by
taking 13 reading for the effort in this range, and using the energy equation, electrical resistivity has been found
for copper oxide and it has been utilized in determining the energy gap according to the general energy equation.
The value of the energy gap of copper oxide using this method (1.6 eV) was also found very close to the
experimental values. The difference in values is due to the presence of a small percentage of impurities in the
sample and this method is effective in the calculation of the energy gap for some semiconductors.

published in International Journal of Renewable Energy Technology Research

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