Hot air balloon gravity homework

AI Thread Summary
A hot air balloon ascends at 3.4 m/s and releases a package at 11 m above the ground. The problem involves calculating the time the package remains in the air using the equation y = y0 + v0*t + 0.5gt^2. The initial attempt yielded a time of 1.88 seconds, but the online homework system marked it incorrect. It's advised to verify the value of gravity, significant figures, and whether units are needed in the final answer.
DrunkAppl

Homework Statement


A hot air balloon is traveling vertically upward at a constant speed of 3.4 m/s. When it is 11 m above the ground, a package is released from the balloon. After it is released, for how long is the package in the air? The acceleration of gravity is 9.8 m/s^2. Answer in units of s.


Homework Equations


y=y0 + v0*t+0.5gt^2
quadratic equation

The Attempt at a Solution


0 = 11 + 3.4t - 4.9t^2
t=1.88 s

But the online homework said it is wrong. Someone check it please
 
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DrunkAppl said:

Homework Statement


A hot air balloon is traveling vertically upward at a constant speed of 3.4 m/s. When it is 11 m above the ground, a package is released from the balloon. After it is released, for how long is the package in the air? The acceleration of gravity is 9.8 m/s^2. Answer in units of s.

Homework Equations


y=y0 + v0*t+0.5gt^2
quadratic equation

The Attempt at a Solution


0 = 11 + 3.4t - 4.9t^2
t=1.88 s

But the online homework said it is wrong. Someone check it please
Your answer is conceptually correct. Online submission programs can be notoriously fickle. Check that you are using the correct value for g, the required number of significant figures and whether units are required in your final answer.
 
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