Physical quantities:
Vector Product or Cross Product: C=AxB
AxB = ABsintheta {just like scalar but instead of cos you use sin)
in case components are given instead of the magnitude of A and B this is needed:
There are three fundamental physical quantities that you need to remember and this should come easy to you
- Mass (kilogram(kg))
- Length (meter(m))
- Time (second(s))
And this is all you need to worry about for now!
Do not forget your vectors from Algebra lesson:
Unit vector: Its basic motive is to just state that it is of length 1 and bears no unit. Do not over think this, whenever the word unit vector pops up or i,j,k comes up wit i-hat(^) remember its of magnitude 1.
Scalar Product or Dot Product: C=A.B {this is the notation}
A.B=ABcostheta {A and B stands for magnitude of A and B, and theta is the angle between A & B from the x-axis}
It is commutative, in other word, A.B=B.A
It can be positive, negative or zero depending on the angle between A & B, if;
0`-90`= + 90`-180`=- and 90`=0 { in this case ` = degree}
Vector Product or Cross Product: C=AxB
AxB = ABsintheta {just like scalar but instead of cos you use sin)
in case components are given instead of the magnitude of A and B this is needed:
Cx=AyBz-AzBy
Cy=AzBx-AxBz
Cz=AxBy-AyBxDo not memorize this, this is really easy to remember. Just remember it has to be C=A1B2-A2B1. You only need to look at the pattern, when looking for Cx, you first use *y and *z (alphabetically) and after - just interchange that. Use whatever comes after what you re looking for, e.g.. looking for Cy, z comes right after and then x. therefore Cy=AzBx-AxBz)
