Physical Science

Question 1

Thermal energy

Answer 1

Thermal energy (also called heat energy) is produced when a rise in temperature causes atoms and molecules to move faster and collide with each other. The energy that comes from the temperature of the heated substance is called thermal energy.

Question 2

Temperature

Answer 2

Temperature is a physical property of matter that quantitatively expresses hot and cold. It is the manifestation of thermal energy, present in all matter, which is the source of the occurrence of heat, a flow of energy, when a body is in contact with another that is colder. Temperature is measured with a thermometer.

Question 3

Heat Transfer

Answer 3

Heat transfer is a discipline of thermal engineering that concerns the generation, use, conversion, and exchange of thermal energy between physical systems. Heat transfer is classified into various mechanisms, such as thermal conduction, thermal convection, thermal radiation, and transfer of energy by phase changes.

Question 4

Fahrenheit

Answer 4

of or denoting a scale of temperature on which water freezes at 32° and boils at 212° under standard conditions.

Question 5

Celsius

Answer 5

of or denoting a scale of temperature on which water freezes at 0° and boils at 100° under standard conditions.

Question 6

Kelvin

Answer 6

the SI base unit of thermodynamic temperature, equal in magnitude to the degree Celsius.

Question 7

Conduction

Answer 7

the process by which heat or electricity is directly transmitted through a substance when there is a difference of temperature or of electrical potential between adjoining regions, without movement of the material.

Question 8

Convection

Answer 8

the movement caused within a fluid by the tendency of hotter and therefore less dense material to rise, and colder, denser material to sink under the influence of gravity, which consequently results in transfer of heat.

Question 9

Radiation

Answer 9

the emission of energy as electromagnetic waves or as moving subatomic particles, especially high-energy particles which cause ionization.

Question 10

Solid

Answer 10

firm and stable in shape; not liquid or fluid.

Question 11

Liquid

Answer 11

A liquid is a nearly in compressible fluid that conforms to the shape of its container but retains a (nearly) constant volume independent of pressure. As such, it is one of the four fundamental states of matter (the others being solid, gas, and plasma), and is the only state with a definite volume but no fixed shape.

Question 12

Gas

Answer 12

a substance or matter in a state in which it will expand freely to fill the whole of a container, having no fixed shape (unlike a solid) and no fixed volume (unlike a liquid).

Question 13

Conductor

Answer 13

a conductor is an object or type of material that allows the flow of charge in one or more directions. Materials made of metal are common electrical conductors.

Question 14

Insulator

Answer 14

a substance which does not readily allow the passage of heat or sound.

Question 15

Conservation of Energy

Answer 15

a principle stating that energy cannot be created or destroyed, but can be altered from one form to another.

Question 16

State (of matter)

Answer 16

state of matter is one of the distinct forms in which matter can exist. Four states of matter are observable in everyday life: solid, liquid, gas, and plasma.