Processing Math: Done

From Mechanics

We assume the starting point is the origin. This means r0=0

The boat first accelerates to a point A say. We first must calculate the position of this point rA.

Using r=ut+21at 2+r0 with,

t=10, u=i+2j and from part a) a=0.5i−j ms−2

rA=(i+2j)10+21(0.5i−j)10 2+0=35i−30j

The next stage has

t=40, a=0, r0=35i−30j, and u=6i−8j as the final position and velocity of the first stage is the initial position and velocity of the second stage.

Using once again r=ut+21at 2+r0 we get

r=(6i−8j)40+0+(35i−30j)=275i−350j

This is the boat´s final position.

The distance from the starting point is the magnitude of this vector,

2752+−3552=445 m