What is the speed of an object that travels from #( -2,1,2) # to #( -3, 0,-7 ) # over #3 s#?

1 Answer
Jan 17, 2016

Answer:

The speed of the object #="distance"/"time"=3.037 " units/s"#

Explanation:

  • If you take the two points as standard form vectors, the distance between them would be the magnitude of the vector of their difference.

So take #vecA=<-2,1,2>, vecB=<-3,0,-7>#

  • #vec(A-B)=<-1,1,9>#
    #|A-B|=sqrt(-1^2+1^2+9^2)#
    #|A-B|=sqrt(83)=9.110#
    #"distance"=9.110#

  • The speed of the object #="distance"/"time"#
    #=9.110/3=3.037 " units/s"#