Explanation:
if two vectors are perpendicular to each other then thier dot product is equal to zero so (2i+3j+8k).(-4i+4j+ak)=0 (2)(-4) +(3)(4)+(8)(a) =0 -8+12+8a=0 4+8a=0 8a=-4


F = ma
F = (6kg) (3.5m/s2)
F = 21 N
Unlike a ball, an atom doesn't have a fixed radius. The radius of an atom can only be found by measuring the distance between the nuclei of two touching atoms, and then halving that distance... Does that answer your question?