Magnetism, Electricity, and Atomic Structure: Key Concepts
What is Magnetism and How is it Characterized?
This phenomenon manifests itself in certain substances (iron, cobalt, and nickel) and is characterized by the appearance of attractive or repulsive forces on other bodies.
What is the Magnetic Field and How is it Measured?
Physical properties generated in a region of space by a magnet or electric current, which exerts a force on charged or magnetized bodies located nearby, are measured in the International System as Teslas.
What are 4 Characteristics of
Read MoreThermodynamic Properties: Monatomic and Diatomic Gases
Deriving Values of Cv, Cp, and γ for Monatomic and Diatomic Gases
Monatomic Gases
For monatomic gases, the internal energy (U) is given by:
U = (3/2) nRT
where n is the number of moles, R is the gas constant, and T is the temperature.
The specific heat capacity at constant volume (Cv) is defined as:
Cv = (∂U/∂T)v
Substituting the expression for U, we get:
Cv = (3/2) nR
The specific heat capacity at constant pressure (Cp) is defined as:
Cp = (∂H/∂T)p
where H is the enthalpy. For an ideal gas, H = U
Atomic Models: From Cathode Rays to Bohr’s Theory
Cathode Rays: Electrons
The study of electrical discharges through gases was the origin of the discovery of the electron. Gases at atmospheric pressure do not normally conduct electric current; they are almost perfect insulators. For example, an electric spark requires an enormous potential of 30,000 V to jump between two spheres separated by 1 cm. If the distance increases, the potential difference required for the spark to jump also increases. However, gases become increasingly good conductors
Read MoreEnergy, Kepler’s Laws, and Fluid Dynamics: Key Concepts
ITEM 5: Energy
Energy is a property of bodies or material systems that produces changes in how people work and/or heat.
- 1 J = 0.24 cal
- 1 J = 103 kJ
- 1 cal = 4.18 J
- 1 kcal = 103 cal
Mechanical energy (EM) is the energy linked to the position or the movement of bodies. There are two types of EM:
EM = Ec + Ep
Ec: The energy that bodies have due to the fact of being in motion. Its value depends on body mass and speed.
Ep: The energy that bodies have because they occupy a certain position. Depending on the body
Understanding Motion, Velocity, and Acceleration in Physics
What is Motion?
Motion is a physical phenomenon defined as any change of position in space that bodies in a system experience with respect to themselves or another body, which is taken as a reference. Any body in motion describes a path. The description and study of a body’s motion require determining its position in space versus time. This requires a reference system.
What is a Frame of Reference?
A reference system or framework is a set of conventions used by an observer to measure the position and
Read MoreGravitational and Electric Fields: Forces and Interactions
Item VIII. Gravitational and Electric Fields
These interaction forces between two bodies are given the name of contact forces.
However, there are many bodies that interact without touching. These interactions are explained by the concept of field.
8.1. Concept of Electric Field and Gravitational Field
The presence of an electric charge alters the space around it to produce an electric force on another charge nearby. Similarly, the presence of a mass alters the space around it so it produces a gravitational
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