-the contact force
-weight of an object
-the surfaces in contact (coefficient of friction).
these are what I think are the answer
Answer:
D. Frozen water is less dense than liquid water.
Explanation:
Titanic sank in the North Atlantic Ocean in the year 1912. There were more than 2000 passengers on board from which about 1500 died.
Frozen water that is ice has less density than liquid water. The density of ice is 
and the density of the water is 
.
Due to this very slight difference in density, ice floats on water. Titanic, on the night of April 14, 1912, crashed into an iceberg around midnight which caused opening of 5 of its watertight compartments. The water filled into the ship and it eventually sank in.
At the initial state: v1 = vf = 0.001053 m
3
/kg, h1 = hf = 467.11 kJ/kg, and s1 = sf = 1.4336 kJ/kgK.
The mass of the water is: m = V/v1 = 0.005/0.001053 = 4.7483 kg.
To find the final state, we will use the First Law:
Q12 = m(h2 - h1) for closed system undergoing a constant pressure process.
h2 = 1Q2/m + h1 = 2200/4.7483 + 467.11 = 930.43 kJ/kg.
At P2 = P1 = 150 kPa, this is a saturated mixture.
hf = 467.11 kJ/kg, hfg = 2226.5 kJ/kg, sf = 1.4336 kJ/kgK, and sfg = 5.7897 kJ/kgK
s2 = sf + sfg (h2 – hf )/hfg = 1.4336 + 5.7897(930.43 – 467.11)/2226.5 = 2.6384 kJ/kgK.
The entropy change of water is:
Delta Ssys= m(s2 – s1) = 4.7483(2.6384 – 1.4336) = 5.72 kJ/K.
