Physics

Estimating I'd say:

1.) b. (Even though the train is moving, the rock won't fall all the way behind. Perhaps slightly off, though.)
2.) a. ( 9.8 m/sec ² of gravity will increase it's speed)
3.) d. ( same as ^ but it will decrease by that much per second)

^_^

Thank you sooo much, and I think you're someone special.

Why thank you, Olive! ^_^

A train is moving a constant velocity. Inside the train, you hold a rock next to your shoulder and let it go, The rock hits the floor.
a) Behind your back b) exactly below your hand c) ahead of your hand

A stone is in free fall downward. At this moment, it's falling at 45 m/s. A second later its downward speed will be about
a)55 m/s b)45 m/s c) 35 m/s d) There's no way to tell

Now, suppose you use slingshot upward with a speed of 25 m/s. two seconds later its speed will be about
a) 50 m/s b)45 m/s c)5 m/s d)12.5 m/s

Hi Olive,
Are you supposed to be using physics formulas, calculus or educated guessing?
Special has certainly got the right ideas.
a) You and the book have initially got the same speed. The books speed doesn't change just because it is dropped (unless there is a big wind or something) so it should drop near your feet.
My prediction is the same as Special's
b) As Special said, it'll get faster . Using calculus I got 54.8m/s ²
c) I am assuming that initially the stone is going straight up. Using calculus I know that after 2 seconds the stone is still going up and the speed is about 5.4m/s
None of these answers take into account air resistance or wind or anything like that.

I hope that you didn't mind me posting this after your answer Special, your answers were correct.

Oh, I don't mind. I really appreciate it when people do that actually, especially if to correct me.

I was thinking about it from a physics stand point (because I'm currently working on that in school). And because there weren't specific variables, I was guessing based on basic laws of physics. ^_^