Question

What is the speed of an object that travels from `( -9,4,-6)` to `( 7,1,-2 )` over `3 s`?

Answer 1

Well it is not said that by which path the object reached its end point from initial point of journey.

Distance is the direct path length which we need to know for calculating speed.

Let's consider that here the object went in a straight line so that displacement=distance

I.e `sqrt((7-(-9))^2 +(1-4)^2 +(-2-(-6))^2)=16.75 m`

So,speed = distance /time = `16.75/3=5.57 ms^-1`