An object is at rest at (2,1,5) and constantly accelerates at a rate of 3ms as it moves to point B. If point B is at (6,7,5), how long will it take for the object to reach point B? Assume that all coordinates are in meters.

1 Answer
Jun 24, 2016

It will take 2.193 seconds.

Explanation:

The distance between two points (x1,y1,z1) and (x2,y2,z2) is given by

(x2x1)2+(y2y1)2+(z2z1)2

Hence distance between (2,1,5) and (6,7,5) is

(62)2+(71)2+(55)2

= 42+62+02=16+36+0=52=213

(As distance covered is given by S=ut+12at2, where u is initial velocity, a is accelaration and t is time taken. If body is at rest S=12at2 and hence t=2Sa

As the coordinates are in meters, the time taken at an acceleration of 3 msec2 will be given by

t=2×2133=4×3.6063=4.808=2.193