AP Physics 1: Algebra-Based Flashcards: Conservation of Energy
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Review key ideas with interactive flashcards. This set includes 14 cards to help you master important concepts.
What principle describes the behavior of a system where mechanical energy is conserved?
The behavior of such a system is described using the principles of conservation of mechanical energy.
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What principle describes the behavior of a system where mechanical energy is conserved?
The behavior of such a system is described using the principles of conservation of mechanical energy.
Consider a falling apple. If the system is just the apple, is its mechanical energy conserved?
No, because the external force of gravity from Earth does work on the system, increasing its kinetic energy.
How does the selection of a system boundary affect the analysis of its energy?
The selection of a system determines whether the energy of that system is considered to change, as it defines what is internal versus external to the system.
What is mechanical energy?
Mechanical energy is the sum of a system's kinetic and potential energies.
What is the universal law regarding energy in all interactions?
Energy is conserved in all interactions; it can be transferred or change forms, but the total amount remains constant.
Consider a falling apple. If the system is the apple AND the Earth, is mechanical energy conserved (ignoring air resistance)?
Yes, because the gravitational force is now internal to the system, and potential energy is converted to kinetic energy within the system.
What does it imply if the total mechanical energy of a system is not constant?
It implies that either work was done on the system by an external force or nonconservative interactions occurred within the system.
Does the conservation of mechanical energy principle apply if there is friction in the system?
No, because friction is a nonconservative interaction, which means mechanical energy is not constant as it is converted into other forms like thermal energy.
Under what two conditions is the total mechanical energy of a system constant?
The total mechanical energy is constant if the work done on the selected system is zero and there are no nonconservative interactions within the system.
How must a change in one type of energy within a system be balanced?
The change must be balanced by an equivalent change of other energy types within the system or by a transfer of energy with the surroundings.
What are the components of a system's energy?
The energies present in a system can include kinetic energy and various forms of potential energy, which together constitute mechanical energy.
Explain the relationship between work done on a system and its mechanical energy.
If the net work done on a system by external, nonconservative forces is non-zero, the total mechanical energy of the system will change.
If a system is composed of only a single object, what is the only type of energy it can have?
A system composed of only a single object can only have kinetic energy.
In an isolated system with no friction, if potential energy decreases by 50 J, what happens to the kinetic energy?
The kinetic energy must increase by an equivalent 50 J to ensure the total mechanical energy of the system remains constant.