Factors influencing interest in STEM careers: An exploratory factor analysis

The results of the research were evaluated in two categories. One of the categories was classical mechanics "Physics I" and the other was electricity and magnetism "Physics II".

When the results of the research in terms of classical mechanics were analyzed, nearly 80% of the students described the symbol and unit of the force while 45% of the students could not write the formula of the force according to Newton' Laws of Motion. Many students did not determine the symbol, unit, and formula of angular velocity, angular acceleration, and angular momentum. When the results of the students were generally evaluated, approximately 25% of the students defined the symbol and unit of the fundamental physical quantities and 20% of the students also could write the formula of the fundamental physical quantities for Physics I.

When the results of the research in terms of electricity and magnetism were analyzed, many students identified the symbol, unit, and formula of the electric potential, capacitance, electric current, and resistance. Numerous students could not write the symbol, unit, and formula of the electric flux, electric flux density, magnetic dipole moment, magnetization and inductance. When the results of the students were generally evaluated, 37% of the students identified the symbol and unit of the fundamental physical quantities and 35% of the students could also write the formula of the fundamental physical quantities for Physics II. These ratios obtained from the data sheet are quite low for science, technology, engineering and mathematics education.

When the results of the first and second research questions were interpreted from technical aspect, the majority of the students had difficulty in determining the symbol and unit of the fundamental physical quantities and they did not usually make the connection between the symbol, unit, and formula of the fundamental physical quantities for Physics I and Physics II.

Some students could not answer the fundamental physical quantities' symbol, unit and formula which torque, heat, impulse, momentum, magnetic dipole, moment, magnetization, and inductance for classical mechanics. Some students had problems by indicating the symbol of the work, power, and impulse. Some students had also difficulty in understanding the differences between electric flux and electric flux density, between electric current and current density, between magnetic flux and magnetic flux density. The results of some studies (Close & Heron, 2011; Lopez, 2003; Mashood & Singh, 2012a; Mashood & Singh, 2012b; Mashood, 2014; Smaill & Rowe, 2012) were supported by the result of the present research.

Many students had difficulty in identifying the symbols of the fundamental physical quantities because the majority of instructors used different symbols for showing the same fundamental physical quantity in Turkey. Therefore some students referred as "d" the symbol of mass density while some students indicated as . They also faced with the similar problems for indicating of the other physical quantities' symbol (impulse "I", current "I"; momentum "p", pressure "P", power "P"; volume "V" electric potential "V"; magnetic flux density "B" and magnetic flux strength "H"). The results of some studies (Goris, 2016; Hekkenberg, 2012; Pablico, 2010; Rowlands, 1997; Smaill & Rowe, 2012) were supported by the findings of the present research. Many students did not remember the formula of fundamental physical quantities both classical mechanics and electricity and magnetism although the usage of symbol, unit and formula of the fundamental physical quantities (mass density, force, weight, electric current, electric potential, resistance, etc.) were taught to the students at every level of education.

The main reason of these problems might be low consciousness of students on using the units and symbols and/or absence of conceptual learning habits. When the indicated problems were generally evaluated, many students seemed reluctant to learn the symbol unit, and formula of the fundamental physical quantities; they preferred to memorize the formula of the physical quantities instead of comprehending the physical quantities; they focused on problem solving without determining the symbol and unit of the given or desired quantities; besides many instructors immediately solved the problems without performing dimensional analysis, showing vector and scalar quantities, explaining given concepts in the problems.

The cognitive and affective opinion of the students about the usage of the essential keys of the fundamental physical quantities were reported as follows: many students thought that the usage of the fundamental physical quantities' symbol, unit, and formula was not necessary to solve problems therefore they did not want to learn the concepts by using the essential keys of the fundamental physical quantities. They believed that the usage of fundamental physical quantities' symbol, unit, and formula was a waste of time by problem solving. On the other hand, several students believed that the usage of the essential keys of the fundamental physical quantities was helpful for problem solving.

Recommendation

Some suggestions based on the results of the research could be presented as follows: The instructors might use common scientific language for presenting of the symbol, unit, and formula of the fundamental physical quantities. They might teach the dimensional analysis and show vector and scalar quantities to the students. They might explain relationships between symbol, unit, and formula of fundamental physical quantities. Besides they might spend more time for conceptual learning. As a result of the presented recommendations, the students may begin to realize the big picture for meaningful learning.