Load weight of radiosonde and shell of a weather balloon is 2.7kg, hydrogen density inside the weather balloon is 0.09 kg/m³, air density is 1.29kg/ m³. For lifting this weather balloon, how much hydrogen is needed at least inside this weather balloon?
Set m as needed hydrogen weight, so G=(2.7+m)g, F=pgv=1.29kg/ m³*9.8N/kg*m/0.09, because G=F, so (2.7+m)g=1.29kg/ m³*9.8N/kg*(m/0.09), so m=0.2025kg.
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Set m as needed hydrogen weight, so G=(2.7+m)g, F=pgv=1.29kg/ m³*9.8N/kg*m/0.09, because G=F, so (2.7+m)g=1.29kg/ m³*9.8N/kg*(m/0.09), so m=0.2025kg.
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