The total energy in the universe is constant. Energy can be transformed from one form to another or transferred from the system to the surroundings (or vice versa), but in the end the total amount of this energy remains the same. A bar chart is a useful tool for illustrating how energy is stored, transferred, and conserved.
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To be successful with this question, you will need to know about the four forms of energy. You will also need to understand the effect of frictional forces and collisions upon the system energy. And it will help to have a good strategy. We can help with all three of these needs. Read on! 

Forms of Energy

Questions in the wizard level will emphasize four different forms of energy. They are described below. Read carefully and take note of the variables that affect each form.

Gravitational Potential Energy (PE_grav): Gravitational potential energy is the stored energy of vertical position resulting from the interaction of the Earth and an object. If the system includes the Earth and the object, then it possesses this form of energy.  The amount depends (in part) on height. Objects at higher positions have more PE_grav than those at lower positions. 

Kinetic Energy (KE): Kinetic energy is the energy of motion. If an object is moving , then it has kinetic energy. The amount of kinetic energy is often inversely related to the amount of gravitational potential energy. For an object moving downhill or falling, the gravitational potential energy will decrease due to the loss of height. In turn, one expects the kinetic energy to increase to offset this loss of PE_grav. In situations like those in the Wizard level, the amount of KE gained is not equal to the amount of PE_grav lost since friction and air resistance tend to dissipate energy from the system. This is discussed later.

Elastic Potential Energy (PE_spring): Elastic potential energy is the energy stored in a compressed or stretched spring. The more the spring is stretched or compressed by the object attached to it, the more elastic potential energy that is stored in the system. Once the object is released from the spring, there is no longer any PE_spring present in the system.

Dissipated Energy (E_dissipated): Dissipated energy is a general category of energy used to describe energy that has been removed from the system due to bouncing, friction, air resistance, or collisions. When an object of the system interacts with its surroundings through these types of forces, mechanical energy is transformed into other forms such as thermal energy and sound energy. The amount of energy that is dissipated will increase over time and the effects of these dissipative forces accumulate. 

 

Frictional and Collision Effects

Kinetic, gravitational potential, and elastic potential energies are all forms of energy that are often described as mechanical energy. Forces acting from outside of the system can cause gains and losses in the total amount of mechanical energy. For instance, friction and air resistance forces most often act against the motion of objects and remove energy from them. Mechanical energy possessed by the system is transformed into thermal energy; we refer to this as dissipated energy. Over the course of time, the amount of energy dissipated from the system will continue to increase until eventually all the kinetic energy is converted to thermal energy (or other dissipated forms) and the object stops. Applying this principle to the diagram provided for this question, you can safely conclude that the E_dissipated at C is greater than the E_dissipated at B which is greater than the E_dissipated at A.

A Good Strategy

All questions in the Wizard level state "Consider the effects of friction, air resistance, and collisions." And in each question, the object eventually comes to a stop due to these effects.  In the final state (location C), the object has no kinetic energy. So the strategy that works best is to start at location C and to determine the proportion of KE (zero), PE_grav, and E_dissipated. The PE_grav may or may not be zero, depending upon the height of the object at location C. For zero-height objects, the PE_grav is 0. For any situation (zero height or non-zero height), the E_dissipated makes up the difference between the PE_grav and the total energy of 10 units.

Once you have identified the bar chart for location C, then begin to work backwards to locations B and A. Observe the heights of locations B and A relative to location C and relative to one another. Many of the six bar chart options can be ruled out just based on PE_grav considerations. Additionally, look at the amount of dissipated energy for the options presented for locations A and B. You know that there should be more dissipated energy for location B relative to A since the amount of energy dissipated accumulates as the object continues to move. While gravitational potential and kinetic energy can decrease and later increase (vice versa) over time, dissipated energy only increases. Using these two rules about the height-PE_grav relationship and the E_dissipated-time relationship, you can pretty much eliminate five of the options and narrow the reasonable options down to one.