# Downward, find airtime, velocity

#### bigman8424

water ballon thrown down at 15m/s to ground 25 m below, what is air time and velocity at impact
y = y(i) + v(i)sint + 1/2gt2
y = 25 + 15sin(90)t + 1/2(-9.8)t2 ? ?

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#### F|234K

dude, try to understand the physics before pluging in numbers into a meaningless equation...read the book first...

#### HallsofIvy

Homework Helper
1. What does "air time" MEAN?
2. More specifically, what ends the "air time"?
3. What is y when the "air time" ends?
4. No, not "y = y(i) + v(i)sint + 1/2gt2 "
5. Do you know what sin(90) is?

6. You need to solve an equation to find the time t when "air time" ends.

#### wisredz

first of all, g is not -9.8. you throw it downwards, not upwards

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