Friction, Photosynthesis, Matter, and Scientist
Friction
Newton’s Laws:
- 1st: An object remains at rest, or in motion at a constant speed in a straight line, unless acted upon by an external force.
- 2nd: Force = Mass * Acceleration
- 3rd: For every action, there is an equal and opposite reaction.
Velocity: Velocity is the speed in combination with the direction of motion of an object.
Positive Acceleration: Positive acceleration occurs when an object is speeding up in the positive direction. For example, if a car is moving forward and its velocity is increasing, it has positive acceleration. This means that the object is gaining speed over time.
Negative Acceleration (Deceleration): Negative acceleration, often referred to as deceleration, occurs when an object is slowing down in the positive direction. For example, when a car is moving forward and its velocity is decreasing, it has negative acceleration. This means that the object is losing speed over time.
Zero Acceleration: Zero acceleration occurs when an object is moving at a constant velocity. If an object’s velocity is not changing, then its acceleration is zero. This can happen when an object is either stationary or moving at a constant speed in a straight line.
Force: Force is an influence that can cause an object to change its velocity, i.e., to accelerate, meaning a change in speed or direction, unless counterbalanced by other forces.
Photosynthesis
Where Does Photosynthesis Occur? – Chloroplast
Where Does Respiration Occur? – Mitochondria
| PHOTOSYNTHESIS | Needed: CO₂, H₂O, Light Energy | Produced: O₂, Sugar (Glucose) |
|---|---|---|
| RESPIRATION | Needed: O₂, Sugar (Glucose) | Produced: CO₂, H₂O, Energy/ATP |
Photosynthesis: The chemical process by which green plants and some other organisms use sunlight to synthesize foods from carbon dioxide and water. Photosynthesis in plants generally involves the pigments chlorophyll A, chlorophyll B, and carotenoids that generate oxygen as a byproduct.
Respiration: It is the process of converting oxygen and glucose into CO₂, H₂O, and Energy/ATP, which allows the process of photosynthesis to begin again.
Matter
Physical Properties: Color, odor, melting point, boiling point, density, refractive index, solubility, hardness, electrical conductivity, thermal conductivity, specific heat capacity, magnetic susceptibility, optical activity.
Dmitri Mendeleev: A Russian chemist and inventor. He is best known for formulating the Periodic Law and creating a version of the periodic table of elements.
Density = Mass / Volume
Density: The density of a substance is the relationship between the mass of the substance and how much space it takes up (volume). The mass of atoms, their size, and how they are arranged determine the density of a substance.
Scientist: Mark Dean
Mark Dean, an eminent computer scientist and engineer, made pivotal contributions to the development of the personal computer. One of his most notable achievements was co-inventing the IBM personal computer, particularly the development of the ISA bus, which allowed multiple devices like printers and modems to be connected to the computer. This innovation significantly expanded the functionality and versatility of personal computers, making them more accessible and practical for everyday use. Dean holds three of the nine original patents for the IBM PC, showcasing his integral role in its creation. In addition to his work on the PC, he was instrumental in developing the first gigahertz chip, which greatly increased the speed and performance of computers. Dean’s contributions extended beyond his technical achievements; he also broke barriers as one of the first African Americans to be named an IBM Fellow, the company’s highest technical honor. His career is marked by numerous accolades and recognitions, reflecting his impact on technology and his role as a trailblazer in the industry. Dean’s journey is not just a tale of technological breakthroughs but also one of perseverance and breaking racial barriers in the tech world.
