Flight times

[aronno]

can anyone explain to me why the flight times are the same (vertical and horizontal) in projectile motion.
Like in a situation such as that of a spring lunching a ball over a table horizontally will have the same times.
I DONT GET IT CAN ANYONE EXPLAIN USING RELEVANT FORMULAS!!!!


thank you  :idiot2:

[Edmund]

Time is a scalar quantity, so it should be same for vertical and horizontal.

[IntoTheNewWorld]

The only force acting on the ball in the downwards direction is gravity in both cases in gravity, the horizontal forces are irrelevant to how long it takes to hit the ground. The force pushing the ball further horizontally doesn't push it down, so it still takes the same time to go down as the ball being dropped.

[kamil9876]

Well you just have to disect what u mean by 'flight time of horizontal component' and 'flight time of vertical component'. I think u mean 'the time it takes for the ball to cover the horizontal component of it's path' for the former; while for the latter u mean 'the time it takes for the ball to go up. then come down(looking at it's y-component only)'.

Now, the amount of time it takes for the ball to travel in the air is the flight time. So subbing t='flight time' into the horizontal component equation gives you the distance it travelled for that time. While subbing it into the vertical component gives u how much displacement the ball has had in that component.

The 'flight time of the two equations' cannot be different since the x and y values of the projectile are changing SIMULTAENOUSLY and so the point at which it hits the ground has some x and y value and those x and y values occur SIMULTAENOUSLY.

Keyword is SIMULTANEITY.