A bar magnet is held in place while another bar magnet is placed near it. The second bar magnet spins around and attaches to the first magnet on one end. Which statement is correct about the energy stored in the magnetic field?
The decrease in the energy stored in the system is proportional to the decrease in kinetic energy.
The increase in the energy stored in the system is proportional to the decrease in kinetic energy.
The increase in the energy stored in the system is proportional to the increase in kinetic energy.
The decrease in the energy stored in the system is proportional to the increase in kinetic energy.
The decrease in the energy stored in the system is proportional to the increase in kinetic energy.
Which of the following factors would decrease the magnetic field strength of an electromagnet?
increasing the distances between the turns of the coil
increasing the current or using a higher-voltage power source
increasing the number of turns in the coil of wire
using an iron core or nail
Increasing the distances between the turns of the coil.
What happens when thermal energy is applied to water?
The water creates steam as soon as thermal energy is applied.
Its molecules gain kinetic energy.
Its molecules lose kinetic energy.
Its molecules gain potential energy.
Its molecules gain kinetic energy.
What is the best description of heat?
thermal energy
the measure of the average kinetic energy of the particles in an object or substance
the transfer of potential energy from one object or substance to another
the transfer of thermal energy from a warmer object or substance to a cooler object or substance
The transfer of thermal energy from a warmer object or substance to a cooler object or substance.
What is the relationship between heat and thermal conductors?
Thermal conductors impede heat, the transfer of thermal energy.
Thermal conductors facilitate heat, the transfer of thermal energy.
Thermal conductors have no effect on heat.
Thermal conductors allow all of the thermal energy in one object or substance to be easily transferred to another object or substance.
Thermal conductors facilitate heat, the transfer of thermal energy.
Which scenario shows radiation?
Eggs boil in a pot of water.
Air warmed by a floor radiator rises to the top of a room, forcing cooler air downward.
Eggs cook in a skillet.
The air under a reading lamp is warmed.