Question

An object is at rest at `(6 ,5 ,9 )` and constantly accelerates at a rate of `4/3 m/s^2` as it moves to point B. If point B is at `(3 ,1 ,4 )`, how long will it take for the object to reach point B? Assume that all coordinates are in meters.

Answer 1

`~~3.25s`

Explanation:

Here displacement = linear distance between the given points
so displacement `s=sqrt((6-3)^2+(5-1)^2+(9-4)^2)=sqrt50m=5sqrt2m`
Initial velocity `u=0`
Acceleration `a=4/3ms^-2`
time taken t=?

So `s=ut+1/2at^2`
`5sqrt2=0*t+1/2*4/3t^2`
`t^2=3/2*5sqrt2~~10.6`
`t ~~sqrt10.6~~3.25s`