# AP Physics 1 homework help

1. Oct 14, 2015

### nenders

1. The problem statement, all variables and given/known data
Problem: Sanjay's air boat starts from rest and accelerates at 9.1 m/s2 for a distance of 216 meters. How fast is it moving at the end of the 216 meters?
And how much time will it take to cover this distance?

Known: Vi = 0m/s

A = 9.1m/s
D = 216m

2. Relevant equations
Vx=Vx0+axt

3. The attempt at a solution
In all honesty I am very confused about this question; any little tips would help! I have tried a few different equations that my teacher has provided us, and each time the question has been wrong. Any ideas on how to approach this kind of question? Any help is appreciated!

2. Oct 14, 2015

### stockzahn

Hi,

the question seem to be tricky, because in the statement the chronological order of the necessary results to solve the problem is reversed. At first you have to calculate the necessary time the ship needs. With this result you can solve the first question with the equation you already provided in 2).

Any ideas about the connectedness between distance, time and a constant acceleration?

3. Oct 14, 2015

### nenders

4. Oct 14, 2015

### stockzahn

Okay, with the formula you provided, you can calculate the velocity of the ship after 1 second, after 2 seconds, after 3 seconds, ...

How can you calculate the travelled distance if you know speed and time?

5. Oct 14, 2015

### nenders

We already know the distance, it's 216m.
Why would we have to calculate it?

6. Oct 14, 2015

### stockzahn

It is to find the equation you need to solve the problem and it is easier to do it step by step. It won't take long. So what would be the velocity of the ship with the given acceleration at

t = 1s: v = ...
t = 2s: v = ...
t = 3s: v = ...

... and if you know the velocity and the time how to calculate a travelled distance?