Homework Help: Newtons Law of motion

1. Nov 28, 2012

mc2_phy

1. The problem statement, all variables and given/known data

A shell is fired at an abgle of 30 degrees to the horizontal. If the shell stays in the air for 40 seconds, calculate
a)how far it lands from it's original position
b)the highest point it can reach

2. Relevant equations

N/a

3. The attempt at a solution
I was unparticularly sure because the q says 40 seonds- should it be 40m/s

2. Nov 28, 2012

grzz

Is

v = v$_{0}$ +gt

a familiar equation?

3. Nov 28, 2012

WillemBouwer

v = u+gt
s = ut + 0.5gt^2
and v^2 = u^2+2gs

make an inventory of what parameter values you have and see which equation suits it best...

4. Nov 28, 2012

mc2_phy

No not really. Just wondering how you solve this.

5. Nov 28, 2012

thank you.