I understand that F=ma, mass is in kilograms and acceleration is metres per second squared so Newtons are just kilograms metres per second squared, but what does that mean? I can’t seem to comprehend it/really understand it intuitively. Why are we adding kilograms, metres per second squared times (or vice-versa)? I understand stuff with division, like density, because it makes sense, like with density, you’re dividing the mass over the volume occupied to see how many kilograms you have per cubic metre of the substance in question, so kg/m^3 , but I seem to have trouble understanding the multiplied quantities, like Newtons.
In: 6
We start with one kilogram. That is a unit of mass. It is stuff.
We want to move it. Which means speeding it up.
To speed it up we have to change how fast it is going.
To know how fast something is going we have to measure how far it has gone in a particular time.
We measure distance in metres, and time in seconds. So how fast something is going is measured in metres per second – how many metres every second. So how quickly we speed up will be how many metres per second our speed is increasing by every second, so metres per second per second, or metres per second-squared.
Putting this all together, 1 kg m s^(-2) means that we are taking one kilogram of mass and every second we are increasing how fast it is going so that at the end of that period it will be travelling one more metre every second than it was at the start of that period.
If you want to understand intuitively why the kg and m are multiplied together, if we have more mass we need to push harder to get it to speed up. If we want it to start going an extra 2m every second for each second we push it, rather than just 1m, we need to push harder.
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