Calculating Force Needed to Hold Down a Hydrogen-Filled Balloon

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To calculate the force needed to hold down a hydrogen-filled balloon, one must first determine the total weight of the balloon and the hydrogen it contains. The buoyancy force of the air acting on the balloon, which is dependent on the volume of hydrogen, must also be considered. It's crucial to remember that force is measured in Newtons while mass is measured in kilograms, as mixing these units can lead to significant errors, especially in academic settings. The discussion highlights the confusion surrounding unit conversions and the importance of using the correct measurements in calculations. Understanding these concepts is essential for accurately solving physics problems related to buoyancy and force.
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A 30kg balloon is filled with 100m^3 of hydrogen. How much force is needed to hold it down??


I'm not even sure which formula to use with this one. :confused:
 
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What is the total weight of the system balloon+hydrogen?
What is the buoyancy force of air associated with 100m^3 volume?
 
got it, thanks...


i guess the biggest problem was that the answer was given in Newtons and i had it in kgs.

Newtons alway smess me up :P

thanks for your help!
 
NB!
Force is measured in Newtons, mass is measured in kgs (in the IS system, that is).

This is completely different concepts, and mixing up units on exams, for example, is a VERY BAD THING (at least in Norway..)
 
arildno said:
NB!
This is completely different concepts, and mixing up units on exams, for example, is a VERY BAD THING (at least in Norway..)

it is the same here in the states...
:biggrin:
 
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