1. The hydrogen balloons which are used to collect weather information from the atmosphere is made of plastic and never completely filled. Thus the pressure inside and outside are same. The balloon is filled with 150 litres of hydrogen, the air temperature is 27°C and the atmospheric pressure is 98 kPa. The balloon rises to a height where it radios back that the pressure is 30kPa and the temperature is - 33°C. i. What is the Kelvin temperature equivalent to 27°C and -33°C? (1 mark) ii. What is the volume of hydrogen at this height? (2 marks)​

- Volume of the balloon is 5.78 L.

Solution:- There are 0.24 moles of hydrogen gas in a balloon at 35 degree C and 1.05 atm pressure. It asks to calculate the volume of the balloon.

This problem is based on ideal gas law equation:

P = 1.05 atm, n = 0.24 mole, T = 35 + 273 = 308 K

R =

V = ?

The equation could be rearranged for the volume as:

Let's plug in the values and do the calculations to get the volume of the balloon:

V = 5.78 L

So, the volume of the gas balloon is 5.78 L.

the minimum amperage that the current in this wire would have to have so that its weight is completely supported by the magnetic force due to earth's field, assuming that no other forces except gravity act on it