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07/08/2026

𝐓𝐡𝐞 𝐂𝐨𝐧𝐜𝐞𝐩𝐭 𝐨𝐟 𝐏𝐡𝐲𝐬𝐢𝐜𝐚𝐥 𝐐𝐮𝐚𝐧𝐭𝐢𝐭𝐢𝐞𝐬

Physical quantities are quantities that have measurable physical properties. (In other words, they can be measured). They consist of numerical values and units.

𝐓𝐡𝐞𝐲 𝐚𝐫𝐞 𝐜𝐥𝐚𝐬𝐬𝐢𝐟𝐢𝐞𝐝 𝐢𝐧𝐭𝐨 𝐭𝐰𝐨:
1. fundamental physical quantities and
2. derived physical quantities.

𝐖𝐡𝐚𝐭 𝐚𝐫𝐞 𝐅𝐮𝐧𝐝𝐚𝐦𝐞𝐧𝐭𝐚𝐥 𝐏𝐡𝐲𝐬𝐢𝐜𝐚𝐥 𝐐𝐮𝐚𝐧𝐭𝐢𝐭𝐢𝐞𝐬?

These are basic quantities that provide the basic units of measurement. The three most common fundamental quantities are: 𝙡𝙚𝙣𝙜𝙩𝙝, 𝙢𝙖𝙨𝙨 and 𝙩𝙞𝙢𝙚.
𝐓𝐡𝐞𝐢𝐫 𝐬𝐭𝐚𝐧𝐝𝐚𝐫𝐝 𝐮𝐧𝐢𝐭𝐬 𝐨𝐟 𝐦𝐞𝐚𝐬𝐮𝐫𝐞𝐦𝐞𝐧𝐭 𝐚𝐫𝐞:
• metre (m) for length
• kilogram (kg) for mass
• second (s) for time.

𝐖𝐡𝐚𝐭 𝐚𝐫𝐞 𝐃𝐞𝐫𝐢𝐯𝐞𝐝 𝐏𝐡𝐲𝐬𝐢𝐜𝐚𝐥 𝐐𝐮𝐚𝐧𝐭𝐢𝐭𝐢𝐞𝐬?

As the name suggests, they are the quantities that are derived by combining two or more 𝙛𝙪𝙣𝙙𝙖𝙢𝙚𝙣𝙩𝙖𝙡 𝙦𝙪𝙖𝙣𝙩𝙞𝙩𝙞𝙚𝙨. Their common examples are:
• velocity (m/s)
• acceleration (m/s^2)
• force (N)
• work (J)
• pressure (N/m^2)

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13/08/2023

𝗧𝗵𝗲 𝗖𝗼𝗻𝗰𝗲𝗽𝘁 𝗼𝗳 𝗥𝗲𝗳𝗹𝗲𝗰𝘁𝗶𝗼𝗻 𝗮𝗻𝗱 𝗶𝘁𝘀 𝗧𝘆𝗽𝗲𝘀

Reflection is a fundamental property of waves, including various types of waves such as light, sound, water waves, and electromagnetic waves. When a wave encounters a boundary or interface between two different mediums, a portion of the wave energy is redirected back into the original medium. This phenomenon is known as 𝘳𝘦𝘧𝘭𝘦𝘤𝘵𝘪𝘰𝘯. Reflection plays a crucial role in many aspects of our daily lives, from simple occurrences like seeing our reflection in a mirror to more complex applications like radar and sonar systems.

𝗧𝘆𝗽𝗲𝘀 𝗼𝗳 𝗥𝗲𝗳𝗹𝗲𝗰𝘁𝗶𝗼𝗻

1. 𝗦𝗽𝗲𝗰𝘂𝗹𝗮𝗿 𝗥𝗲𝗳𝗹𝗲𝗰𝘁𝗶𝗼𝗻: Specular reflection occurs when a wave interacts with a smooth and flat surface. In this type of reflection, the incident waves strike the surface and reflect in an organized manner, maintaining their parallel alignment. This results in a clear and well-defined reflection, such as what we see when looking at ourselves in a flat mirror.

2. 𝗗𝗶𝗳𝗳𝘂𝘀𝗲 𝗥𝗲𝗳𝗹𝗲𝗰𝘁𝗶𝗼𝗻: Diffuse reflection takes place when a wave interacts with a rough or irregular surface. Unlike specular reflection, the incident waves strike the surface and scatter in multiple directions. As a result, the reflection appears to be less defined, and the energy is spread over a wider area. For instance, the reflection of light on a piece of paper or a rough wall is an example of diffuse reflection.

18/07/2023

𝗣𝗥𝗢𝗣𝗘𝗥𝗧𝗜𝗘𝗦 𝗢𝗙 𝗪𝗔𝗩𝗘𝗦

𝗥𝗲𝗳𝗹𝗲𝗰𝘁𝗶𝗼𝗻: Reflection occurs when a wave encounters a boundary or obstacle and bounces back. The angle of incidence (the angle between the incident wave and the normal to the surface) is equal to the angle of reflection (the angle between the reflected wave and the normal). Examples of reflection include light waves reflecting off a mirror or sound waves bouncing off a solid surface.

𝗥𝗲𝗳𝗿𝗮𝗰𝘁𝗶𝗼𝗻: Refraction is the bending of waves as they pass from one medium to another with different properties, such as density or refractive index. The change in speed of the wave causes it to change direction. This phenomenon is observed when light passes through a prism, causing the different colors to separate, or when a straw appears bent when partially immersed in water.

𝗗𝗶𝗳𝗳𝗿𝗮𝗰𝘁𝗶𝗼𝗻: Diffraction refers to the bending or spreading out of waves when they encounter an obstacle or pass through a narrow opening. It occurs when the size of the obstacle or opening is comparable to the wavelength of the wave. Diffraction is observed in various phenomena, such as when light passes through a narrow slit, causing it to spread out into a pattern of dark and light bands called a diffraction pattern.

𝗜𝗻𝘁𝗲𝗿𝗳𝗲𝗿𝗲𝗻𝗰𝗲: Interference is the interaction of two or more waves that occupy the same space at the same time. It can result in either constructive interference, where waves combine to form a larger amplitude, or destructive interference, where waves cancel each other out and reduce the overall amplitude. Interference is responsible for various phenomena, including the colorful patterns seen in soap bubbles and the alternating bright and dark regions in an interference pattern produced by light passing through two closely spaced slits (Young's double-slit experiment).

𝗣𝗼𝗹𝗮𝗿𝗶𝘇𝗮𝘁𝗶𝗼𝗻: Polarization refers to the orientation of the electric field vector of a transverse wave. Waves can be unpolarized (randomly oriented electric field) or polarized (electric field aligned in a specific direction). Polarization can be achieved by filtering out waves that are not aligned with a desired orientation or by scattering. Polarized light, for example, is commonly used in 3D glasses, sunglasses, and LCD screens.

𝘐𝘵 𝘪𝘴 𝘸𝘰𝘳𝘵𝘩 𝘯𝘰𝘵𝘪𝘯𝘨 𝘵𝘰 𝘬𝘯𝘰𝘸 𝘵𝘩𝘢𝘵 𝘵𝘩𝘦𝘴𝘦 𝘱𝘳𝘰𝘱𝘦𝘳𝘵𝘪𝘦𝘴 𝘱𝘭𝘢𝘺 𝘤𝘳𝘶𝘤𝘪𝘢𝘭 𝘳𝘰𝘭𝘦𝘴 𝘪𝘯 𝘶𝘯𝘥𝘦𝘳𝘴𝘵𝘢𝘯𝘥𝘪𝘯𝘨 𝘢𝘯𝘥 𝘦𝘹𝘱𝘭𝘢𝘪𝘯𝘪𝘯𝘨 𝘵𝘩𝘦 𝘣𝘦𝘩𝘢𝘷𝘪𝘰𝘳 𝘰𝘧 𝘸𝘢𝘷𝘦𝘴 𝘪𝘯 𝘥𝘪𝘧𝘧𝘦𝘳𝘦𝘯𝘵 𝘤𝘰𝘯𝘵𝘦𝘹𝘵𝘴, 𝘪𝘯𝘤𝘭𝘶𝘥𝘪𝘯𝘨 𝘰𝘱𝘵𝘪𝘤𝘴, 𝘢𝘤𝘰𝘶𝘴𝘵𝘪𝘤𝘴, 𝘢𝘯𝘥 𝘷𝘢𝘳𝘪𝘰𝘶𝘴 𝘰𝘵𝘩𝘦𝘳 𝘧𝘪𝘦𝘭𝘥𝘴 𝘰𝘧 𝘴𝘤𝘪𝘦𝘯𝘤𝘦 𝘢𝘯𝘥 𝘦𝘯𝘨𝘪𝘯𝘦𝘦𝘳𝘪𝘯𝘨.