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

1 Answer
Mar 27, 2017

The time is =3.89s

Explanation:

The distance between the 2 points A=(2,1,3) and B=(9,3,5) is

d=sqrt((9-2)^2+(3-1)^2+(5-3)^2)

=sqrt(49+4+4)

=sqrt57

The acceleration is

a(t)=1

The velocity is

v(t)=int_0^t1dt=t

The distance is

s=int_0^t tdt=1/2t^2

This is equal to

sqrt57=1/2t^2

t^2=2sqrt57=15.1

So,

t=sqrt15.1=3.89s