Notes, abstracts, papers, exams and problems of Physics

The Scientific Method

1. How to Ask a Question?

2. Formulate a Hypothesis

3. Investigation Design (Experimentation)

4. Observe, Measure, and Collect Data

5. Analyze and Perform Results using data tables

6. Contrast Your Hypothesis

7. Share Results and Draw a Conclusion

Fundamental Units

Length: meter (m) Mass: kilogram (kg)

Time: second (s) Temperature: kelvin (K)

Derived Units

Area: square meter (m²) Volume: cubic meter (m³)

Speed: meters per second (m/s)

Acceleration: meters per second square (m/s²)

1 atm: 760 mmHg, 1013 mb, 101325 Pa

The Future of Physics

Science Fiction and Reality

Much of what we see in science fiction, such as time travel, warp drive, higher dimensions, portals through space and time, stargates, and wormholes, is actually within the realm of possibility according to the laws of physics.

Imagine meeting your grandparents in the year 1900, when they were simple farmers. Consider the powers of Greek gods: Zeus could control objects with his mind, materializing them at will. Venus possessed a perfect, ageless body. We are now beginning to understand the genetics of aging at the molecular level.

Apollo rode his chariot across the heavens. We will eventually have the flying cars we've always dreamed of. By the year 2100, we may have powers comparable to the gods.... Continue reading "The Power of Physics: From Aristotle to the Future" »

• Thermal energy is the energy that is exchanged between two bodies or systems of matter that have different temperatures. Thermal energy is also exchanged when a body changes from one physical state to another.

• Kinetic energy (Ec) is the energy of a body in motion. It depends on the mass and the speed of the body.

• Potential energy (Ep) is the energy of a body determined by its position. It depends on the body’s mass and position

• Gravitational Potential Energy
• Elastic potential energy

• Electrical energy is energy produced by the movement of charged particles (electrons), due to a potential difference.

• Radiant energy is energy carried by the electromagnetic waves, such as light, radio waves, microwaves, X-ray or γ rays. It’s called radiation. 

• Chemical

Relativity Law and Phenomena

The relativity law, analyzing phenomena for bodies whose speed is comparable to the speed of light

The time and the space can have a different reference system

Characteristics of Light

The light is reflected and has wave characteristics.

The measurement can be probabilistic and not precisely directs.

Measurement and Physical Magnitude

Measurement: the act of measuring as the comparison of a property or physical magnitude with another of the same class. Assigning a numerical value to the result of said measurement, and adding a unit of measurement which will give us an accurate idea of the physical magnitude that is being measured

Physical Magnitude: is the term associated with some property or characteristic measurable... Continue reading "Understanding Relativity and Measurement in Physics" »

Linear Kinetics

Law 1 of Inertia: object at rest and no external forces acting on it remains at rest, object in motion stays in motion, object at rest stays at rest, Law 2 of Acceleration: Change in motion is proportional to the force impressed and is made in direction of straight line. Force causes acceleration Law of Reaction: forces never act in isolation, but in pairs, forces equal to magnitude, in opposite direction. Conservation of Momentum: momentum before impact equals momentum after impact Impulse-momemtum: Ft=m(VF-VI) M=mv I=Ft

Torques & Moments

Torque: turnin effect produced by force aka moment, angular or rotary force, directly proportional to magnitude of force. Motion of a restrained system, force applied away from axis. Moment

Chapter 1: Dimensional Analysis and Measurement

Understanding Dimensions and Models

Dimensional analysis is a method used to verify the correctness of physical relationships by examining the dimensions of the quantities involved. A model is a representation or analogy that helps us understand complex phenomena by relating them to something familiar.

Trigonometry and Accuracy

Trigonometry, the study of triangles and their relationships, plays a crucial role in physics. Accuracy refers to how close a measurement is to the true value.

SI Units and the Search for Order

The International System of Units (SI) provides standardized units for scientific measurements. The SI unit of time is the second, the unit of length is the meter, and the unit of mass... Continue reading "Understanding Physics Concepts: Motion, Measurement, and Mathematical Tools" »

Gravity Method

The weight of any body depends on the force of gravity at that location.

The force of gravity varies with elevation, rock density, latitude, and topography.

When a mass is suspended from a spring, the amount of spring stretching is proportional to the force of gravity.

F=m.g

Where:

• g: Acceleration of gravity.

Since mass is constant, then stretch variations determine the variations in the acceleration of gravity (g).

A gravimeter is an instrument used to measure (g) at stations. The readings are corrected for elevation, latitude, and topography. The normal value of (g) is subtracted from the corrected readings to compute the residual gravity.

The values of residual gravity are plotted at the measuring stations to produce a contour map... Continue reading "Gravity, Magnetic, and Seismic Geophysical Methods" »

Understanding Light

What is Light?

Light is a form of electromagnetic energy. Very small particles called photons move in a wave pattern.

Visible light is the light which allows you to see the colours and shapes of objects. Light can come from a natural source or an artificial source.

Some objects only emit light which they receive from other light sources. In this case, they absorb some of the light, and reflect the rest in all directions.

Objects can be transparent, translucent, or opaque. This depends on how light travels through them.

How Does Light Travel?

Light travels in a straight line. It travels in waves and does not require a medium. The speed of light, however, does depend on the medium. The speed of light in a vacuum and in the air is... Continue reading "Understanding Light: Reflection, Refraction, and More" »

Is 1984 fiction or reality?

Orwell’s novel narrates the life of Winston Smith: a dissatisfied citizen under the control of a violent, totalitarian government. In a society where love is forbidden and every action is watched, Smith finds solace in a forbidden love affair; a small act of rebellion in a world he cannot control. It is within Smith’s journey of defiance, as he becomes a target of the government, that Orwell weaves his own political analysis.

1984 is a frightening example of a totalitarian government. This government of unchallenged power controls not only the present and future of its people, but also the past. Many times the Party, the name of the government, alters the past to suit its needs. Orwell's vision is frightening because... Continue reading "1984: Fiction or Reality?" »