Question

What is the magnitude of the resultant of the forces F1=-3i+2j-k, F2=2i-j+3k and F3=3i+j-k measured in dynes ?

Answer 1

$\vec{F_1}=-3i+2j-k$

$\vec{F_2}=2i-j+3k$

$\vec{F_1}=3i+j-k$

$\text{the resultant force is the vector sum of all forces}$

$\vec{F}=\vec{F_1}+\vec{F_2}+\vec{F_3}$

$\vec{F}= -3i+2j-k+2i-j+3k+3i+j-k$

$\vec{F}=2i+2j+k$

$|\vec{F}|=\sqrt{2^2+2^2+1}=3$

$\text{the default force is measured in newtons}$

$1J=10^5dyn$

Answer:$\vec{F}=2i+2j+k \ ;|\vec{F}|=3*10^5dyn$