# Physics

# ○ The Unit Circle ○

## ○ The Unit Circle 📺

This

**video**explains how to use the**unit circle**to define the**trigonometric ratios**of**sine**,**cosine**, and**tangent**for all real numbers.

This

**video**explains how for**acute angles**(in**Quadrant I**), the two different definitions of the trigonometric values (**SOH****CAH****TOA**:**S**in=**O**pposite/**H**ypotenuse,**C**osine=**A**djacent/**H**ypotenuse, and**T**an=**O**pposite/**A**djacent) and the**unit circle definition**result in the same values.

# 〰️ Orders of Magnitude 〰️

## 〰️ Orders of Magnitude 📺

This

**video**describes what is meant by an**order of magnitude**, in which situations they are used, and how to**estimate sizes in terms of order of magnitude**.

This

**video**applies**orders of magnitude**to a practical example: finding the height of Mount Everest.

This

**video**applies**orders of magnitude**to a practical example: finding the Earth's diameter.

# 🔁 Motion Problems 🔁

This

**video**defines the difference between**displacement**and**distance**. The**definite integral of a velocity function**gives us the**displacement**. To find the**actual distance traveled**, we need to use the**speed function**, which is the**absolute value of the velocity**.

This

**video**explains the relationship between**position**,**velocity**, and**acceleration**. If**position**is given by a function**p(t)**, then the**velocity, v(t),**is the**first derivative**of that function, and the**acceleration, a(t)**is the**second derivative**. This concept is covered in our**mathematics**and**physics**courses.

This

**study guide**defines:**distance**,**speed**and**acceleration**,**force and pressure**,**work**,**energy**,**conservation of energy**(**potential**and**kinetic**energy) and the**equivalence of work and energy**.

This

**video**provides a basic introduction to**pressure**.**Pressure**is defined as**force per unit area**.**1 Pascal equals 1 Newton of force per square meter of area**. It also discusses the**inverse relationship**between**elevation**and**atmospheric pressure**. As the**elevation increases**, the**atmospheric pressure decreases**and the**boiling point of water decreases**.

## 🔵 Física, Physics Khan Academy Videos en Español 📺

This link has numerous

**video**tutorials from the**Khan Academy en Español**, covering such concepts in**Physics**as: Movement in One Dimension, Two-Dimensional Movement, Newton's Forces and Laws of Motion, Centripetal Force and Gravitation, Work and Energy, Impact and Linear Momentum, Torque and Angular Momentum, Oscillations and Mechanical Waves, Fluids, Thermodynamics, Electric Charge, Field and Potential, Circuits, Magnetic Forces and Fields. Faraday's Law, Electromagnetic Waves and Interference, Geometric Optics, Special Relativity, Quantum Physics, and Discoveries and Projects (Magnetism, Batteries, and Resistors).