ChatterBank2 mins ago
Canonball!
A train is travelling at exactly 20mph in a perfectly straight line, with a canon pointing directly upwards, all natural factors are obsolite.
The canon shoots a canonball 20 meter's in the air.
Where would the ball land?
Answers
No best answer has yet been selected by thecoach. Once a best answer has been selected, it will be shown here.
For more on marking an answer as the "Best Answer", please visit our FAQ.Perhaps there is a simpler way to understand this. If the train were stationary, it must be agreed that the ball will fall back into the cannon. If the train is moving at 20mph, then the ball leaves the cannon with a forward velocity of 20mph. If it is accepted, for this argument, that air resistance is not a factor, then there is nothing to reduce this forward motion. The ball continues to move forward at 20mph, as does the train, so the ball returns to the cannon.
ABC312�s contention that there is no further force propelling the ball forward is quite correct, but similarly there is no force acting to reduce its forward speed either, so it continues forward at 20mph.
One word fatgaz, ABC, Relativity!
Viewed from the train the ball goes up then down, viewed from the ground the ball traces an arc through the sky from cannon back to cannon.
That Einstein geezer new his onions!
Nothing is actually stationary so all movement,speed etc is relative. How fast am I going typing this? Well 1000mph on the Earth, 60000mph orbiting the sun, relative to the desk 0!