A teaching story: constant speed with no forces acting
Teaching Guidance
for 14-16
Newton's first law
Imagine taking your worst enemy in a space craft to get rid of them in the farthest corner of the universe (way beyond Sunderland). On arrival at the farthest corner, you open the cargo-hold of the space craft, position your worst enemy on the edge of the decking and give them a gentle nudge out into space. The nudge is just sufficient to send them drifting away from the craft. As they travel away they neither speed up nor slow down, since there are no forces acting upon them. As they drift away into blissful eternity, never to be seen again, you muse on the fact that their motion is a stunning validation of Newton's first law.