An object is at rest at (9 ,1 ,3 ) and constantly accelerates at a rate of 1/4 m/s^2 as it moves to point B. If point B is at (6 ,8 ,2 ), how long will it take for the object to reach point B? Assume that all coordinates are in meters.

1 Answer
Aug 11, 2017

The time is =15.7s

Explanation:

The distance AB is

AB=sqrt((6-9)^2+(8-1)^2+(2-3)^2)=sqrt((-3)^2+(7)^2+(-1)^2)

=sqrt(9+49+1)=sqrt59m

The acceleration is a=1/4ms^-2

The initial velocity is u=0ms^-1

We apply the equation of motion

s=ut+1/2at^2

So,

sqrt59=0+1/2*(1/4)^2*t^2

t^2=32sqrt59

t=sqrt(32sqrt59)=15.7s