There are not a great many types of calculation you will be asked to do at this level. You may be asked about speed, density, pressure or perhaps calculating weight from mass and the force of gravity. The question will usually give you enough information for you to work out what sums you need to do. I find that the most important thing to remember is the key unit associated with each type of calculation. This will give you the other units you will need.
For example, if you want to calculate speed in m/s, then you already know that you need to divide metres (distance) by seconds (time). You can use a formula triangle to help you to rearrange the equation. I have made this animated gif to help explain.
Similar triangles can be used to help with density and pressure.
You may also be asked to convert between weight (in newton) and mass (in gram). For example, on Earth gravity is about 10 N/kg. What does a 45 kg statue weigh on Earth? 45 kg x 10 N/kg = 450 N
If you get these equations firmly set in your memory it will hold you in very good stead for the future.
Questions…
- What equation calculates distance if you know speed and time?
- What equation calculates mass if you know density and volume?
- What equation calculates pressure if you know weight and area?
- What equation calculates volume if you know mass and density?
- What equation calculates mass if you know force (weight) and gravity?
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