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

1 Answer
Jul 3, 2018

The time is =5.98s

Explanation:

The distance AB is

d_(AB)=sqrt((6-5)^2+(9-2)^2+(2-1)^2)

=sqrt(1^2+7^2+1^2)

=sqrt(1+49+1)

=sqrt(51)m

The acceleration is a=2/5ms^-2

The initial velocity u=0

Apply the equation of motion

s=ut+1/2at^2

sqrt(51)=0+1/2*2/5*t^2

t^2=5sqrt(51)

t=sqrt(5sqrt(51))=5.98s

The time is =5.98s