Question

An astronaut is "floating" outside of the space station orbiting the Earth. He holds two identical gas cylinders. One is full of gas the other empty - but he doesn't know which is which. Suggest five different, realistic ways he could determine which one is full. Each way you think of should exploit a different physical principle. In each case state the physical principle at play and any assumptions you make.

Answer 1

i) Using spring : He can measure by frequency of oscillation in spring.

ii) Attraction of other masses towards cylinders: The heavier cylinder exerts more force on other objects, so attracts more

iii).They calculate force instead, using a dual-springed device called the Space Linear Acceleration Mass Measurement Device (SLAMMD).As the name suggests, it slams a constant (though relatively small) force against the astronaut in question. From there, it's a simple matter of using Newton's Second Law of Motion to calculate mass.

iv) Using pendulum: small pendulumd can be tied near each cylinders. The cylinder having larger mass will have smaller time period.

v) Simply by using beam balance: putting one cylinder in one pan, other in other. The heavier cylinder exerts more torque