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elaborate on the changes in molecular motion of particles as they change from solid to liquid to gas.
question 16 options:
as the phase changes occur, the freedom of motion of the particles increases.
as the phase changes occur, the freedom of motion of the particles decreases.
as the phase changes occur, the freedom of motion of the particles compresses.
as the phase changes occur, the freedom of motion of the particles is constant.

The answer is A because As the phase changes occur, the freedom of motion of the particles increases.

the minimum constant speed at which she can catch the train is 2.7 m/s

given:

acceleration = 0.6

time = 4.5 s

to find:

velocity = ?

formula used:

from 1st kinematic equation we get,

v = u + at

u = initial speed of train = 0 m/s

v = final speed of the train

a = acceleration of the train

t = time

solution:

from 1st kinematic equation we get,

v = u + at

u = initial speed of train = 0 m/s

v = final speed of the train

a = acceleration of the train

t = time

v = 0 + (0.6 × 4.5)

v = 2.7 m/s

the minimum constant speed at which she can catch the train is 2.7 m/s