heat and energy 1- 1.2

Under what conditions does thermal-energy transfer between objects at different temperatures?

- In an isolated system, heat always transfers thermal energy spontaneously from high temperature to low temperature. No process transfers energy from low temperature to a higher temperature without work being done.

Under what conditions does thermal-energy transfer between objects at different temperatures?

- thermal energy flows from higher temperature to lower temperature. - The objects must be in thermal contact

How does thermal-energy transfer(heat) cause substances to change state?

As energy is added to a substance, either the kinetic energy of its particles increases or a phase change occurs.

what are three temperature scales that are commonly used?

Fahrenheit, Celsius, Kelvin

Under what conditions does thermal-energy transfer between objects at different temperatures?

Heat transfers energy until thermal equilibrium is reached.

an example of conduction is what?

Is heating one end of an iron bar. Soon, the other end of the bar becomes hot.

Adding thermal energy to a substance does what?

It increases its temperature or changes its state

At the phase change the temperature does what?

It stays constant until the added or removed thermal energy completes the phase change.

what are the common units used to measure thermal energy?

Joules and Calories

How can two objects of different masses have the same temperature but different amounts of thermal energy?

Substances have characteristic specific heat values.

What is the difference between thermal energy and temperature?

Thermal energy is the total kinetic energy of the particles that make up a substance. Temperature is a measure of the average kinetic energy of the particles in a substance. Temperature tells us how cold or hot something is, heat is measured of thermal energy in transit.

What are some examples that show how thermal energy is transferred by means of conduction, convection and radiation?

Thermal energy is transferred by conduction, convection and radiation.

an example of convection is what?

is the upward flow of air above a room heater.

an example of radiation is what?

is the warmth felt near a hot fire.

Radiation is the transfer of what?

it is the transfer of thermal energy by electromagnetic radiation.

convection works best with what?

liquids and gasses

conductions works best with what?

solids and less with liquids.