# Question: a lifesaver device has an outer diameter of 75 cm...

###### Question details

A lifesaver device has an outer diameter of 75 cm and an inner
diameter of 45 cm. Its total weight is 2 kg and it is used in water
at 20 ^{O}C. Assuming, for simplicity, that the thickness
of the life saver is constant at 12 cm.

a) Determine the maximum weight (in N) that the life saver can hold before it sinks.

b) Determine its force due to surface tension (in N) and discuss whether it significantly affects the force balance performed in a).