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SI Prefixes mnemonic

SI Prefixes

Need to convert between prefixes like from picosecond to microsecond? Or kilometer to milimeter? Do you need to memorize the SI prefixes? Find it difficult to remember the letters/symbols, sequence and exponent value? If you answered yes, then you are not alone. My students join you in this struggle. That’s why I developed a mnemonic to help them memorize all 12 prefixes they need for the course. So, here we go, introducing the 12 prefixes: – Tera – Giga – Mega – kilo – hecto – deca – deci – centi – mili – micro – nano – pico – Here’s the thing, each of these prefixes have their own abbreviation/symbol. The first three (Tera, Giga, Mega) are abbreviated with 1 upper case letter (T, G and M, respectively). Then, the rest are 1 lower case letter (k, h, d, c, m, n, p), except deca (da) […]

Density formula

Density – Why should we care?

What is density? It’s mass divided by volume. The more mass you can fit into a fixed space, the denser it is. Let’s say we have two same size boxes. We stuff in feathers in one of the boxes and stones in the other box of the same size. Which is denser? Of course, the box with stones is denser since stones weigh more than feathers. So why is density important? Can you think of an example or two that involve density? Density can affect whether something will float or not (hot air balloon, boat, ice in drinks), which layer will be on top (oil spill in the ocean, lava lamp, vinaigrette), identity/purity of a substance (purity gold), to name a few. It’s present in our daily lives more than we may have realized. I relatedthree […]

Flow chart for classification of matter

Classification of Matter

Pure substance and mixture. Element and compound. Homogeneous mixture and heterogeneous mixture. How are they different? Does it MATTER? Yes! WHY? How to classify them? You’re in luck! Ask two questions and you can easily classify matter into element, compound, homogeneous mixture and heterogeneous mixture. Let me show you how. Let’s classify one of the recipe I’m going to try. Looks like I’ll be grilling the seasoned chicken on aluminum pan and cover it with aluminum foil. Before that, I’ll need to season it with salt, tumeric powder and other spices. Let’s start with aluminum foil. Refer to the flow chart at the top for the series of questions and classification.  The first question we should always ask is, “Does it have fixed composition?” Do we know what aluminum foil is made out of? Yea, it’s […]

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