Fundamental Concepts of Physics and Measurement

What is Physics?

Physics is the science that aims at studying the properties of substances and their interactions, in order to explain the general properties of bodies and natural phenomena without changing their nature.

What is Scientific Notation?

Scientific notation is the process whereby a number can be written as the product of two factors, where the first factor is a number between 1 and 10 and the second factor is a power of base 10.

What is Power?

In physics, power is the amount of work done per unit of time.

What are Units?

Units refer to an arbitrary amount to which the value 1 is assigned.

What is Measurement?

Measurement is the basic process of science that involves comparing a selected pattern with the object whose physical magnitude is being measured, to see how many times the pattern is contained in that magnitude.

What is Isolating Variables?

Isolating a variable (often referred to as clearing a variable) from any expression means leaving it alone on one side of the equality.

What are Space, Matter, and Time?

• Space: According to physics, space is where a body can be occupied, which can describe the trajectory of the body and should be described vectorially under the system adopted by convention.
• Matter: Matter is anything that occupies space.
• Time: Time is the physical quantity that measures the duration or separation of events subject to change within the systems under observation; i.e., the period between the state of the system when state X appeared and the instant that X shows a perceptible change for an observer (or measuring apparatus).

Features of a Measurement Pattern

1. Must be uniform: This means that the pattern must have the same characteristics as the measured quantity. It is impossible to measure the length of a mass or a liter.
2. Must be easy to handle.
3. Must be indestructible and undeformable: Even when destroyed, it should always be possible to rebuild. It must be undeformable to be stored through time without suffering changes.
4. Must be universal: It should be accepted internationally so that scientific dialogue can be established. Using different patterns results in totally different measures.

What are Magnitudes?

A magnitude is defined as any property that can be measured.

Classification of Magnitudes

Magnitudes are classified into fundamental and derived:

• Fundamental magnitudes: Those that are not derived from other quantities and cannot be defined with respect to other quantities, through which physics can be described. Example: length, mass, time, etc.
• Derived magnitudes: Those that come from the combination of fundamental values through mathematical relationships.

Classification of Units

Units are classified into fundamental, derived, and secondary:

• Fundamental Units: The units of the fundamental values, chosen freely as the bases for fixing the system.
• Derived Units: Those that come from the combination of the fundamental units.
• Secondary Units: These are the multiples and sub-multiples of the fundamental and derived units.