"If it were..." (not "if it was...")

You're kidding, right?

Nope. "Were" is used with a subjunctive ("contrary to fact") condition.
"The sky isn't blue, but if it were, I could fly today."

I didn't know masses changed.

Except for nuclear reactions and high speeds, they don't. "Conserved"
(in physics) refers to a quantity the same before and after. For
example, a point can change how far north it is from another point
simply by changing the reference frame (magnetic, true), but the
distance is conserved.

In the statement I made about mass, "constant" works just as well, but
"conserved" is more to the point, as we are changing reference frame.

If it doesn't weigh anything, why is it falling?

It isn't. It's remaining right where it is. Only in the earth's
reference frame is it falling (accelerating downwards). But the earth's
frame is not the free-falling one I was talking about. In the reference
frame of the falling object, nothing at all is happening to it. It's
staying right where it is. ("Where are you?" "I'm right here. I'm
always 'right here', why do you keep asking!")

Jose
--
"There are 3 secrets to the perfect landing. Unfortunately, nobody knows
what they are." - (mike).
for Email, make the obvious change in the address.