Science Cafe - How many balloons would it really take for Roald Dahl's Mrs Twit to lift off? - ÃÛÑ¿´«Ã½ Sounds

Science Cafe - How many balloons would it really take for Roald Dahl's Mrs Twit to lift off? - ÃÛÑ¿´«Ã½ Sounds
How many balloons would it really take for Roald Dahl's Mrs Twit to lift off?
John Rutledge investigates the science behind Roald Dahl's stories