Question

It isn't possible to see the molecules of an object without special equipment but knowing the density of an object helps us predict what we can't see if water has a density of 1kg/m and The molecules look like the image below describe what the molecules might look like for the samples on either side compared to water molecules in lead will be

Answer 1

F
g
​
=M
sub
​
⋅gF, start subscript, g, end subscript, equals, M, start subscript, s, u, b, end subscript, dot, g
where g is the acceleration due to gravity, 9.8 m/s/s. But you know that gravity isn’t the only force that acts on the submarine. There must be a buoyant force that acts to counteract it. The submarine is filled with air (like a balloon), so you expect it would float on top of the water were it not for the action of its propeller: even though the steel walls of the submarine make it heavy, this added weight is offset by a huge amount of trapped air. This effect is similar to a balloon, which doesn’t float until it’s filled with air. The submarine thus requires a propeller that acts together with gravity to make the submarine sink, despite the buoyant force acting on it.