Posted by **Rachelle** on Friday, April 20, 2012 at 7:49pm.

Snoopy is in his plane, 4500 ft above ground. he fires a projectile straight up. The Vo of the projectile is 340 ft/s. (after the projectile is fired, it has no acceleration, so its height can be modeled by a "falling body" model). The Red baron is maintaining a constant altitude of 5200ft.

1. Write an equation describing the upward motion of the projectile.

***No air resistance.

***Let y represent altitude of the projectile (feet).

***let t represent time after firing in sec.

~~ 5200=-16t^2+340t+4500~~ IS THAT EQUATION CORRECT?

2. When, on the way up, might the projectile intersect the Red Baron? (THIS IS WHERE IM STUCK).

- Applying Algebraic Thinking to Data -
**Steve**, Saturday, April 21, 2012 at 5:57am
since we have no idea of the speed of the planes, we can only assume yu need to find when the height of the projectile is 5200 ft. Then ,if Snoopy is extremely lucky, he just might hit the Red Baron.

So, since your equation is correct, just solve

y = -16t^2+340t+4500

when y = 5200, as you showed above.

What's the problem? It's just a simple quadratic.

5200=-16t^2+340t+4500

-16t^2+340t-700 = 0

t = 5/8 (17 ± √177)

- Applying Algebraic Thinking to Data -
**Steve**, Saturday, April 21, 2012 at 5:59am
at t = 5/8 (17 - √177) the missile is going up

at t = t = 5/8 (17 + √177) it is coming back down.

To see this, go to wolframalpha . com and type in

solve 5200=-16t^2+340t+4500

## Answer this Question

## Related Questions

- Physics - A projectile is fired straight up from a cliff which is 200 feet above...
- Math - A projectile is fired straight up from a cliff which is 200 feet above ...
- physics - a projectile is fired from the top of a building with an initial ...
- Physics - A projectile is fired from ground level with a speed of 40 m/s at an ...
- PHYSICS - A Projectile IS FIRED FROM THE TOP OF A BUILDING WITH AN INITIAL ...
- Physics - A projectile is fired with an initial speed of 31.0 at an angle of 10....
- Physics - A projectile is fired with an initial speed of 28.0 m/s at an angle of...
- math - A projectile is fired directly upward with a muzzle velocity of 860 feet ...
- Physics - Q Exactly 2.7s after a projectile is fired into the air from the ...
- physics - a projectile with a muzzle velocity of 550 m/s is fired from the a gun...

More Related Questions