Question

Any help? It's velocity and position sort of stuff.
http://oi60.tinypic.com/21msxlz.jpg
The question is in the link since it's a picture.

Answer 1

ok so lets break this problem down. The first thing you need to find out is where john starts. According to the problem, the mailbox is 1 m in front of him.

Answer 2

Right

Answer 3

the problem states that the mailbox is the zero location, meaning that it is designated as position 0 m, and that any position that john takes is relative to that position (e.g. at 2 m he is 2 meters in front of the mailbox, - 4 m is 4 meters behind the mailbox.)

Answer 4

So if we know that the mailbox is 1 meter in front of john, that means he is 1 m behind the mailbox.

Answer 5

So what would be his position at time 0?

Answer 6

2m?

Answer 7

Not exactly. It would be -1 m. He is 1 m behind the mailbox, so if we use it as a reference point, it would be measured as -1 m.

Answer 8

Is that clear or is it still confusing?

Answer 9

Oh

Answer 10

A little more clear but physics kinda confuses me in general.

Answer 11

Well thats ok, its hard at first but once you take the time to actually think through it. It makes a lot of sense.

Answer 12

I get why it's -1 for the first one but I don't know how you would figure out the rest though.

Answer 13

Ok so next part.

Answer 14

We need to examine the velocity graph

Answer 15

position tells you where you are, and velocity tells you where you are going

Answer 16

So if we look at the velocity of john at t = 0. We find that he is moving at rate of - 2 m/s.

Answer 17

The graph goes positive so does that mean he's going away from it?

Answer 18

It depends. Just looking at whether its positive or negative isn't enough.

Answer 19

His position at t = 0 is -1 m. His velocity is -2 m/s at t =0. The negative velocity and negative position tells you that he will be moving further from the mailbox.