Any Physics genius' on this board?

[cyismydog]

I need help with a problem for my AP online class, my teacher is a bigger idiot than Pacman Jones, and can't teach to save her life:

A cannonball is fired from a cliff 140 m high downward at an angle of 27 degrees with respect to the horizontal. If the cannon's muzzle velocity is 34 m/s, what is the cannon ball's speed when it hits the ground?

Any help would be appreciated. You don't necessarily have to do it for me, but just show me which equations to use, and which variables mean what.
Thanks in advance, I really appreciate it.

 

[tim_redd]

What planet is this cannon fired from?

 

[cyismydog]

What planet is this cannon fired from?

Earth.

 

[3TrueFans]

European or African Cannonball?

 

[CycoCyclone]

Are we taking gravity into account?

 

[IcSyU]

How hard is the ground? :wink: If it's hard enough, it's gonna be 0. :biggrin:

 

[sodakjoe]

Equation for constant acceleration

at^2 + v0t + s = 0, where:

a = acceleration
v0 = initial velocity of the object
s = initial position of the object

 

[Stewo]

You know I don't speak Spanish, CIMD.

 

[sodakjoe]

Split your velocity into two components: an x component and a y component, and try to work it from there.

 

[keepngoal]

Has resistance been taken out of the problem?

 

[cyismydog]

Has resistance been taken out of the problem?

Yes.

 

[pyrocyz]

Things that need to be taken into account include terminal velocity (you would need the mass of the cannon ball), gravity in general (the cannon ball may be traveling almost straight down by the time it gets to the ground)

Personally I would look into projectile motion equations. All projectiles proceed on a curve, you are just starting 60% of the way through the curve.

 

[DaddyMac]

European or African Cannonball?

Has resistance been taken out of the problem?

Clearly a French cannonball.


Next question is how did it get to England?

 

[pyrocyz]

I'd listen to sodakjoe...he knows his stuff

 

[cyfanatic]

I have nothing to offer this thread in terms of an answer...but what does it say about me that I am curious to see what the answer is? I keep hitting refresh to see if someone has offered an answer...

 

[cyismydog]

Things that need to be taken into account include terminal velocity (you would need the mass of the cannon ball), gravity in general (the cannon ball may be traveling almost straight down by the time it gets to the ground)

Personally I would look into projectile motion equations. All projectiles proceed on a curve, you are just starting 60% of the way through the curve.

That's what I'm trying to do, use the projectile motion equation, but once i plugged all the numbers in, the computer said the answer was wrong, but you get three shots at each problem.

 

[jdoggivjc]

I'd listen to sodakjoe...he knows his stuff

He's no physics expert - he stayed at a Holiday Inn Express last night...

 

[sodakjoe]

He's no physics expert - he stayed at a Holiday Inn Express last night...

Haha. I did not stay at a HIE last night, and I am far from an "expert".

 

[3TrueFans]

Haha. I did not stay at a HIE last night, and I am far from an "expert".

Just look at his avatar. Is that not a face you would trust with your physics questions?

 

[tim_redd]

Just look at his avatar. Is that not a face you would trust with your physics questions?

He's smart to wear a helmet to protect his brain from zombies.