Energy/ Temperature/conductors/insulators/heat transfer/speed. Flashcards
How do we measure temperature and what is the unit of measurement?
Thermometer
Degrees Celsius
What is energy and what are the units of measurement?
There are different forms of energy: Internal Kinetic Elastic potential gravitational potential Electrical Magnetic
The unit of energy is Joules.
Which would take longer to cook a bigger can of baked beans or a smaller can of bake beans?
The bigger can because a smaller volume takes a shorter amount of time to cook where as a bigger volume take a long amount of time to cook.
How is heat energy transferred in solids?
Conduction - the particles vibrate and the internal energy increases - this makes adjacent particles vibrate more and so the increase in internal energy and therefore temperature passes thorough the substance form the hot end to the cold end.
Metal teaspoon in hot drink - the end out of the liquid gets hot.
A good conductor transfers energy easily.
A poor conductor is an INSULATOR.
Heat transfer will continue from the hotter object to the colder object until they are at the same temperature and thee is THERMAL EQUILIBRIUM..
What does insulator mean?
An insulator it something that prevents transfer of heat and therefore prevents heat loss or gain.
The vacuum in a flask keeps fluids hot or cold.
What is conduction? Give an example.
It is a method of transferring heat but there must be a connection between what ever is being heated and the heat source. If you put your hand on the aga the heat is being transferred into your hand.
Good conductors e.g. Metal
good insulators e.g. Air, vacuum, clothing
What is internal energy and what affects it?
Internal energy is produced as a result of the movement of particles in an object.
When an object is heated, the particles move more vigorously and the internal energy and therefore the temperature increases.
Unless an object changes state (melts or boils) the temperature will continue to increase.
The greater the volume of an object, the greater the internal energy.
What is radiation?
All objects transfer energy to their surroundings by infrared radiation.
The hotter an object is the more infrared radiation is emitted.
No particles are involved in transfer of energy by radiation, transfer occurs by waves. It is not limited by distance or contact from the object e.g. Warming effect of the sun.
What is a convection current and give an example?
A convection current is a transfer of heat energy in liquids and gases.
Water in a kettle is heated, the molecules at the bottom vibrate and move more vigorously and rise being replaced by the cooler molecules which are now warmed.
A radiator warms the air molecules next to it, they vibrate and move apart, the air becomes lighter and rises and is replaced by the cooler, more dense air molecules which are now warmed.
What is the sum for speed?
D Distance over speed x time.
➖➖
SxT
What is the temperature of an object?
The temperature of an object is how hot or cold it is.
What are the factors affecting heating fluids or objects?
The volume of the substance- the larger the volume the longer it takes to reach a given temperature.
The temperature you want to heat it to - the higher the target temperature, the longer it takes to achieve it.
How is heat energy transferred in liquids or gases?
Convection.
The movement of warm and cold liquid or gas creates a CONVECTION CURRENT- explain.
How is heat energy transmitted in liquids and gases?
Convection
What sort of surface is good at emitting and absorbing infrared radiation?
Matt, black surfaces.
