An object is at rest at (3 ,5 ,1 ) and constantly accelerates at a rate of 4/3 m/s^2 as it moves to point B. If point B is at (7 ,9 ,2 ), how long will it take for the object to reach point B? Assume that all coordinates are in meters.

1 Answer
Mar 17, 2017

The time taken is =2.94s

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=4/3ms^-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=(3,5,1) and B=(7,9,2)

So,

s=sqrt((7-3)^2+(9-5)^2+(2-1)^2)

=sqrt(16+16+1)

=sqrt33

From the equation of motion,

t^2=(2s)/a

t^2=(2*sqrt33)/(4/3)=8.62

t=sqrt8.62=2.94s