The density of water at 0ºc is very nearly 1000kg/m3 (it is actually 999.84 kg/m3), whereas the density of ice at 0ºc is 917 kg/m3. calculate the pressure necessary to keep ice from expanding when it freezes, neglecting the effect such a large pressure would have on the freezing temperature. (this problem gives you only an indication of how large the forces associated with freezing water might be.) (b) what are the implications of this result for biological cells that are frozen

1.8 x 10⁸ N / m²

Explanation:

Volume of 1000 kg of water = 1 m³

Volume of 1000 kg of ice = 1 / .917 = 1.09 m³

Change in volume = .09 m³

Volume strain = Change in volume / original volume = .09 / 1 = .09

Bulk modulus of elasticity of ice is 2 x 10⁹ N / m²

a ) Bulk modulus = change in pressure / volume strain

change in pressure = bulk modulus x volume strain.

Change in pressure = 2 x 10⁹ x .09 = 1.8 x 10⁸ N./ m².

When water inside the cell freezes it creates huge pressure on the cell wall

breaking it . Even walls of many internal structures of cell are broken leading it to die.

the box does not move because you need to use a force greater than 300 n. you are only using 50 n. it needs to at least be 301 n for the box to move because then it is an unbalanced force and it will move the way that the greater force is pushing it. if you use only 300 n it will be a balanced force and will not move because the force you are exerting on the   box is the same as its force.

hope this !

im sorry if i went too in depth, i am going to include a link to a video on khan academy that will explain this.   hope that you like the video and that it explains more in detail to you.

that is the link.