College Physics 2 - Final Exam

What is convection in heat transfer?

The transfer of heat between liquids and gasses.

Describe the physical significance of “absolute zero” in thermodynamics and if it’s attainable.

It is tied to the average kinetic energy of particles; at absolute zero, a system would reach its minimum possible thermal energy, meaning all particle motion stops; this is impossible and can never be attained.

What does the pressure of an ideal gas depend on?

Temperature, volume, and the number of particles/moles of gas present.

What is the first law of thermodynamics?

Energy cannot be created or destroyed, it can only change forms.

Why can thermodynamics be considered the foundation of physics?

It lays out the basic principles that govern logic of matter.

What does the second law of thermodynamics indicate?

Entropy (disorder) will always increase.

What is the difference between electric potential energy and electric potential? (think in terms of charge)

Electric potential is the energy unit per charge, while electric potential energy is the actual energy of a specific charge placed in that potential.

What is the difference between electric force and electric field? (think in terms of charge)

Electric field is force per unit charge (independent of q), while electric force is the actual force on a specific charge (depends on q).

What does equipotential surface refer to?

The locations in space in which electric potentials are equal.

How is capacitance similar to a battery?

Both involve storing and using charge and potential difference, but a capacitor stores charge directly, while a battery maintains a voltage by continuously moving charge using chemical energy.

Define electric field.

The spaces where electric force may act.

Why is it that the net flux of electric field passing through an enclosed Gauss surface, in which the surface encloses a positive and negative charge, equals zero?

The net electric flux through a closed surface depends only on the total enclosed charge, and since the positive and negative charges cancel out, the net is zero.

A resistor normally converts electrical energy into what form of energy transfer?

Heat.

Name two variables that electric power depends on.

Voltage and current.

Give a biomedical example of resistance.

Blood vessel resistance (smaller radius vessels = much higher resistance); cell membrane resistance (lipid bilayer resists ion flow unless channels are open).