# 7th physics

posted by .

baloonist drops rock from balloon. takes 7 seconds for the rock to fall. what's the balloonist's altitude in feet?

• 7th physics -

It will depend upon whether the balloon is rising or falling when the rock is released.

If the balloon altitude is constant at release of the rock,

Y = (g/2)*t^2
is the distance it falls in time t

g = 32.2 ft/s^2 t = 7 s

Solve for the altitude Y

## Similar Questions

1. ### physics

On Earth a rock falls an unknown vertical distance from a resting position and lands in a lake. If it takes the rock 2.5 seconds to fall, how high is the cliff that the rock fell from?
2. ### Math

You drop a rock off a bridge. The rock’s height, h (in feet above the water), after t seconds is modeled by h = -16t2 + 541. What is the height of the rock after 2 seconds?
3. ### Physics

A rock is thrown horizontally off of a cliff. It starts with a velocity of 4.2 m/s and the cliff is 68.2 m high. How long does the rock fall?

A rock is thrown horizontally off of a cliff. It starts with a velocity of 4.2 m/s and the cliff is 68.2 m high. How long does the rock fall?
5. ### physics 1

An astronaut is stranded on another planet with UNKNOWN GRAVITY. He conducts two experiments. In the first, he drops a rock from a cliff and he finds that it takes the rock 4.15 seconds to reach the ground at the base of the cliff. …
6. ### Physics

An astronaut is stranded on another planet with UNKNOWN GRAVITY. He conducts two experiments. In the first, he drops a rock from a cliff and he finds that it takes the rock 4.15 seconds to reach the ground at the base of the cliff. …
7. ### physics

a person in a hot air balloon ascending vertically at a constant rate of 12m/s drops a rock over the side when the balloon is 40 m above the ground, what is the velocity of the rock just before it hits the ground, and how long will …
8. ### physics

a person in a hot air balloon ascending vertically at a constant rate of 12m/s drops a rock over the side when the balloon is 40m above the ground, what is the velocity of the rock just before it hits the ground, how long will it take …
9. ### physics

a person in a hot air balloon ascending vertically at a constant rate of 12mm/s drops a rock over the side when the balloon is 40m above the ground how long will it take the rock to reach the ground
10. ### Physics

Suppose Jessica drops a rock from a hot air balloon 200m above the water. how long does it take the rock to fall (a) the first 100 meters and (b) the second 100 meters?

More Similar Questions

Post a New Question