Particles of a certain state of matter undergo a phase change.
Before the change, particles of this state matter are easily
compressible and after the change, the particles become
closely packed. The phase change is:

In which situation is the acceleration of a car negative? question 5 options: a)the velocity of a car was 75 km/hr over 4 hours. b)the velocity of a car reduced from 50 km/hr over one minute. c)the velocity of a car increased from 40 km. h to 75 km/h over 15 minutes. d)the velocity of a car was 45 km/hr at 2: 00pm and at 4: 00pm its velocity was 85 km/ht.

Which best describes the difference between internal and thermal energy?

During cooling, the kinetic energy of the molecules falls. why does this happen? a. the motion of the molecules increases. b. the motion of the molecules slows down. c. the van der waals forces between molecules decrease d. the forces of attraction between the molecules are overcome.