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Flashcards in Test 2 Deck (45):
1

Atom

the smallest particle of an element that has all of the element's chemical properties.

2

Electron

A negatively charged particle that whizzes about within an atom

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Atomic nucleus

the core of an atom, consisting of two basic subatomic particles--protons and neutrons.

4

Neutron

An electrically neutral particle in the nucleus of an atom

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Proton

a positively charged particle in the nucleus of an atom

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Element

A pure substance that consists of only one kind of atom

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Ion

an electrically charged atom; an atom with an excess or deficiency of electrons

8

Isotopes

Atoms of the same element that contain different numbers of neutrons

9

Compound

a material in which atoms of different elements are chemically bonded to one another

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Mixture

a substance whose components are mixed together without combining chemically

11

Molecule

two or more atoms that bond together by a sharing of electrons. Atoms combine to become molecules

12

Antimatter

a "complementary" form of matter composed of atoms that have negative nuclei and positive electrons

13

Dark matter

unseen and unidentified matter that is evidenced by its gravitational pull on stars in the galaxies. Dark matter along with dark energy constitutes perhaps 96% of the stuff of the universe

14

Atomic bonding

the locking together of atoms to form larger structures, including solids

15

Density

the mass of a substance per unit volume:
Density = mass / volume

16

Weight density

weight per unit volume:
Weight density = weight / volume

17

Scaling

The study of how size affects the relationships among weights, strength, and surface area.

18

Pressure

the ratio of force to the area over which that force is distributes:
Pressure = force / area
Liquid pressure = weight density X depth

19

Buoyant force

the net upward force that a fluid exerts on an immersed object

20

Archimedes' Principle

an immersed body is buoyed up by a force equal to the weight of the fluid it displaces.

21

Principle of flotation

a floating object displaces a weight of fluid equal to its own weight.

22

Pascal's Principle

the pressure applied to a motionless fluid confined in a container is transmitted undiminished throughout the fluid.

23

Surface tension

the tendency of the surface of a liquid to contract in area and thus behave like a stretch elastic membrane

24

Capillarity

The rise of a liquid in a fine, hollow tube or in a narrow space.

25

Barometer

A device that measures atmospheric pressure

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Archimedes' Principle (for air)

an object in the air is buoyed up with a force equal to the weight of the displaced air.

27

Bernoulli's principle

where the speed of a fluid increases, the internal pressure in the fluid decreases

28

Plasma

An electrified gas that contains ions and free electrons most of the matter int eh rivers is in the plasma phase.

29

heat

the energy that flows from a substance of nighter temperature to a substance of lower temperature, commonly measured in calories or joules.

30

Internal energy

the total of all molecular energies, kinetic plus potential, that are internal to a substance.

31

Specific heat capacity

the quantity of heat per unit mass required to raise the temperature of a substance by 1 Celsius degree

32

conduction

the transfer of heat energy by molecular and electron collisions within a substance (especially a solid).

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Convection

the transfer of heat energy in a gas or liquid by means of currents in the heated fluid. The fluid moves carrying energy with it

34

Radiation

the transfer of energy by means of electromagnetic waves

35

Terrestrial radiation

the radiation emitted by Earth to outer space

36

Newtons's law of cooling

the rate of loss of heat from a warm object is proportional to the temperature difference between the object and its surroundings

37

Solar power

energy per unit time received from the sun

38

Evaporation

the change of phase from liquid to gaseous

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Sublimation

the change of phase from solid to gaseous, bypassing the liquid phase

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condensation

the change of phase from gaseous to liquid

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boiling

the rapid evaporation that takes place within a liquid as well as at its surface.

42

Regelation

the process of melting under pressure ad then subsequently refreezing when the pressure is removed

43

Heat pump

a device that transfers heat out of a cool environment and into a warm environment.

44

Thermodynamics

the study of heat and its transformation into different forms of energy

45

Heat engine

a device that uses heat as input and provides work as output