On vector operation There are dot multiplication and cross multiplication in vector operation. What's the difference and connection between them? For example, in the moment M = f * l, why can't dot multiplication be used instead of cross multiplication? I know that the direction is determined by the right-hand screw rule. Is the size a simple multiplication?

In physics, work and power are calculated by the scalar product of two vectors. W = f · s, P = f · v,
In physics, the moment and Lorentz force are calculated by the vector product of two vectors. M = R × F, f = QV × B
W = f · s = the size of F X the size of s x cos,
The size of M = R × f = R x the size of F X sin
Represents the angle between F and S. represents the angle between R and F

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