What is the speed of an object that travels from ( 6, -3, 1)  to (-1,5,-1 )  over 4 s?

Jan 15, 2016

It is only possible to infer the average velocity.

${\text{Average speed" = sqrt{117}/4 "s}}^{- 1}$

Explanation:

$\text{Displacement} = - 7 i + 8 j - 2 k$

${\text{Average velocity" = (-7/4i + 2j - 1/2k)"s}}^{- 1}$

$\text{Distance travelled} = \sqrt{{\left(- 7\right)}^{2} + {8}^{2} + {\left(- 2\right)}^{2}}$

$= \sqrt{117}$

${\text{Average speed" = sqrt{117}/4 "s}}^{- 1}$