Ice floats in water at 0°C. Why is this an example of physical equilibrium? a)The system is closed; nothing leaves the system. b)No new substances form when the water molecules change state. c)The forward and reverse processes occur at different rates.

Option (b) is the correct answer.

Explanation:

Physical equilibrium is defined as a system in which there will occur no change in the physical state of substance. For example, at zero degree celsius water is present in both liquid and solid state as follows.

For a system to be present in physical equilibrium is as follows.

The system must be a closed system.

It should be dynamic in nature.

There will occur no change in measurable property along with change in time.

Thus, we can conclude that ice floats in water at this an example of physical equilibrium because no new substances form when the water molecules change state.

adding a(n) to an electric circuit would increase the magnetic field around a wire;

b. solenoid

a solenoid is a type of electromagnet whose purpose is to generate a controlled magnetic field.

if the purpose of the solenoid is instead to impede changes in the electric current, a solenoid can be more specifically classified as an inductor rather than an electromagnet.

answer would be letter choice (a),   a ball resting on a shelf. would be another example of potential energy   >   stored energy > not moving.

a ball spinning on a finger   >   kinetic energy > moving energy

a ball rolling on the ground   >   kinetic energy   > moving energy

a   ball flying through the air   > kinetic energy   >   moving energy

hope that                                         : )