Question

What is the speed of an object that travels from `( 7,-8,1)` to `( -1,4,-6 )` over `2 s`?

Answer 1

`v~=8,02 m/s`

Explanation:

`"1- we must find distance between the point of (7,-8,1)"` `" and (-1,4,-6)"`
`Delta s=sqrt((-1-7)^2+(4+8)^2+(-6-1)^2)`
`Delta s=sqrt(64+144+49)" "Delta s=sqrt257 " m"`
`"2- now, we can calculate speed using : " v=(Delta s)/(Delta t)`
`v=sqrt 257/2`
`v~=8,02 m/s`