## General Science Flash Card Set 7286

 Cards 10 Topics Acidity, Atom, Base Units, Bones & Cartilage, Kinetic Energy, Lungs, Power, The Sun, Velocity, Weight

#### Study Guide

###### Acidity

An acid is a substance that gives up positively charged hydrogen ions (H+) when dissolved in water. A base (alkaline) gives up negatively charged hydroxide ions (OH-) when dissolved in water. pH is a scale that measures of how basic or acidic a solution is. Numbered from 0 to 14, solutions with a pH of 7 are neutral, less than 7 are acidic, more than 7 are alkaline.

###### Atom

An atom is the smallest component of an element that still retains the properties of the element.

###### Base Units
Measurement Base Unit Example
length / distance meter (m) km
mass gram (g) kg
volume liter (L) mL
volume (medical) cubic centimeter (cc) cc
time second (s), minute (min), hour (h) ms, min, h

###### Bones & Cartilage

Hard bones provide primary support for the endoskeleton while more flexible cartilage is found at the end of all bones, at the joints, and in the nose and ears. In addition to providing support and protecting bodily organs, bones also produce blood cells and store minerals like calcium.

###### Kinetic Energy

Kinetic energy is the energy posessed by a moving object. Potential energy is stored energy in a stationary object based on its location, position, shape, or state.

###### Lungs

The trachea branches into the left and right bronchi which each lead to a lung where the bronchi subdivide into smaller tubes called bronchioles. Each bronchiole ends in a small sac called an alveolus which allows oxygen from the air to enter the bloodstream via tiny blood vessels called capillaries.

###### Power

Power is the rate at which work is performed or work per unit time: $$P = {w \over t}$$ and is measured in watts (W).

###### The Sun

The Sun is a G-type main-sequence star (G2V) but is informally known as a yellow dwarf star. Composed of 73% hydrogen and 25% helium, the hot plasma that makes up the Sun reaches 9,900°F (5,505°C) at the surface. It formed approximately 4.6 billion years ago and makes up 99.86% of the mass in the solar system.

###### Velocity

Velocity is the rate at which an object changes position. Rate is measured in time and position is measured in displacement so the formula for velocity becomes $$\vec{v} = { \vec{d} \over t }$$

###### Weight

Weight is a force that describes the attraction of gravity on an object. Force is measured in newtons (N) with 1 N being the force required to impart an acceleration of 1 m/s2 to a mass of 1 kg.