An object is at rest at (8 ,2 ,9 ) and constantly accelerates at a rate of 3 m/s as it moves to point B. If point B is at (6 ,7 ,3 ), how long will it take for the object to reach point B? Assume that all coordinates are in meters.

1 Answer
Mar 19, 2017

The time is =2.32s

Explanation:

We are going to apply the following equation of motion :

s=u_0t+1/2at^2

u_0=0

So,

s=1/2at^2

a=3ms^-2

The distance between 2 points A=(x_1,y_1,z_1) and B=(x_2.y_2.z_2) is

=sqrt((x_2-x_1)^2+(y_2-y_1)^2+(z_2-z_1)^2)

Here,

A=(8,2,9) and B=(6,7,3)

So,

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

=sqrt(4+25+36)

=sqrt65

From the equation of motion,

t^2=(2s)/a

t^2=(2*sqrt65)/(3)=5.37

t=sqrt5.37=2.32s