I'm assuming we're applying the standard Integral form of the calculation of work. The solution is provided in the image.
Answer:
When argon changes from a gas to a liquid, the forces between the molecules become stronger so the particles become closer together and come into come into contact more often. The particles move at a less faster rate as the have less kinetic energy due to decrease in temperature. When argon changes from a liquid to a solid, the forces become even stronger so the particles are arranged in fixed positions and vibrate around a fixed point as they cannot move past each other
Frictional force always opposes applied force, so the net force on the cart would have to be 19N - 1.7N. The acceleration can then be solved by using the relation: F = ma. This is shown below:
Net force = 19 - 1.7 = 17.3 N
Acceleration = Force / mass
Acceleration = 17.3 / 2
Acceleration = 8.65 N/m
