A. The molecules start packed together very tightly in a solid. Then when it turns to water, the molecules can move around each other freely, but still contained. When water turns to vapor, the molecules are going crazy moving around. They are not contained at all and bounce of of each other freely.
b. The temperature rises. (ice turns to water at 33 degrees and water turns to vapor at 212 degrees)
It holds the atoms together (aka your last option)
a) Work done = Net Kinetic Energy
= 1/2 x 50 kg x ((12m/s)^2 - (3m/s)^2)
= 0.5 x 50 Kg x (144 -9)(m/s)^2
= 3375 Kg (m/s)^2
b) Force = mxa
a = 120 N/50 Kg = 2.4 m/s^2
Using newtons third law of motion, we get-
V^2 - U^2 = 2 x a x S
S= (12^2-3^2)m^2/s^2/(2 x 2.4 m/s^2)
= 28.125 m
power out / power in so 230/420 = 0.547619048 using sigfiges its about .55 or 55%
It is because of the buoyang force
