This paper deals with the effects of electromagnetic forces on the orbital motion of a spacecraft. The electrostatic charge which a spacecraft generates on its surface in the Earth's magnetic field will be subject to a perturbative Lorentz force. A model incorporating all Lorentz forces as a function of orbital elements has been developed on the basis of magnetic and electric fields. This Lorentz force can be used to modify or perturb the spacecraft's orbits. Lagrange's planetary equations in the Gauss variational form are derived using the Lorentz force as a perturbation to a Keplerian orbit. Our approach incorporates orbital inclination and the true anomaly. The numerical results of Lagrange's planetary equations for some operational satellites show that the perturbation in the orbital elements of the spacecraft is a second order perturbation for a certain value of charge. The effect of the Lorentz force due to its magnetic component is three times that of the Lorentz force due to its electric component. In addition, the numerical results confirm that the strong effects are due to the Lorentz force in a polar orbit, which is consistent with realistic physical phenomena that occur in polar orbits. The results confirm that the magnitude of the Lorentz force depends on the amount of charge. This means that we can use artificial charging to create a force to control the attitude and orbital motion of a spacecraft.

In light of the research objective and hypotheses, the researcher reached the following results: - There is a statistically significant difference at the level (0.05) between the average scores of the experimental group students who study Arabic grammar according to the linguistic analysis strategy and the average scores of the control group students who study Arabic grammar according to the usual (traditional) method in the concept acquisition test Grammar and for the benefit of the experimental group. The researcher followed the experimental design with two equal groups: the experimental and the control, with two tests, pre and post tests. When Al-Ameen Intermediate School for Boys, Division (B), became a control group, its students are taught in the usual way, as the research sample reached (60) students, which included two divisions. Subordinate to Al-Ameen Intermediate School for Boys (30) students of the control group. The researcher used the grammatical concepts acquisition test and the research tool. In light of the results, the researcher reached a number of conclusions, including: - The possibility of applying the linguistic analysis strategy to second-grade intermediate students in Arabic grammar The necessity of providing teachers with a book that includes all modern methods of teaching, including the linguistic analysis strategy, to choose the method that suits the teacher.

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In recent years, studying Lorentz’s force has become a possible good means to control the spacecraft to reduce the fuel cost by modulating spacecraft electrostatic charge (magnetic and electric fields). The generation of Lorentz force is finite by the natural magnetic field and the relative velocity of the spacecraft. Therefore, the Lorentz force cannot fully occur from conventional propulsion technologies. Previous studies are concerned with studying Lorentz’s strength in the magnetic field only.In this work, we developed a mathematical model for a new technique establishing a raise in the level of charging in the spacecraft surface that is moving in the Earth’s magnetic field and provided by modulating spacecraft’s electrostatic charge that induces acceleration via the Lorentz force. The acceleration will be used to find the relationship between capacitance and power required to minimize the consumption of control energy used in such cases or to replace the usual control thruster by Lorentz force.