# An object is at rest at #(7 ,8 ,4 )# and constantly accelerates at a rate of #5/4 m/s^2# as it moves to point B. If point B is at #(1 ,5 ,3 )#, how long will it take for the object to reach point B? Assume that all coordinates are in meters.

##### 1 Answer

It takes 3.29 seconds.

#### Explanation:

First of all we need to know how much distance the objects has to travel. The distance between two points is given by the Pitagora's theorem in 3 dimensions

in our case

Now that we know that our body will travel for 6.78 m we can use the equation of motion for an accelerating body that is

where

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