Question

What is the speed of an object that travels from `( -1, 7,2)` to `( -3, 4,7 )` over `2 s`?

Answer 1

`v=sqrt 10`

Explanation:

`"distance between two point is given as:"`
`x=sqrt(Delta x^2+Delta y^2+ Delta z^2`
`Delta x=x_2-x_1=-3+1=-2`
`Delta y=y_2-y_1=4-7=-3`
`Delta z=z_2-z_1=-3-2`=-5
`x=sqrt((-2)^2⁺(-3)^2+(-5)^2)`
`x=sqrt (4+9+25)`
`x=sqrt40`
`v=x/t`
`v=sqrt 40/2`
`v=sqrt (4*10)/2=2*sqrt 10/2`
`v=sqrt 10`