Physics Definitions

Front 1

Displacement

Back 1

Distance moved in a particular direction

Front 2

Speed

Back 2

Distance traveled per unit time

Front 3

Velocity

Back 3

Distance traveled in a particular direction per unit time

Front 4

Acceleration

Back 4

Rate of change of velocity

Front 5

Newton's first law of motion

Back 5

Every body will continue in it's state of rest, or with uniform velocity unless acted on by a resultant force

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Newton's second law of motion

Back 6

For a body of constant mass, it's acceleration is directly proportional to the resultant force applied on it

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Newton's third law of motion

Back 7

Whenever one body exerts a force on another, the second body exerts an equal and opposite reaction force

Front 8

Mass

Back 8

Measure of inertia of a body

Front 9

Weight

Back 9

Gravitational force exerted on an objects mass

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Force

Back 10

Rate of change of momentum

Front 11

Principle of conservation of momentum

Back 11

If no external force acts on a system, the total momentum of the system remains constant

Front 12

Elastic Collisions

Back 12

A collision in which both the total momentum, and the total kinetic energy of a system is conserved

Front 13

Inelastic Collisions

Back 13

A collision in which the total momentum is conserved, but total kinetic energy isn't

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Upthrust

Back 14

Resultant force on a submerged object due to the upward pressure of the fluid applied on it

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Center of gravity

Back 15

The point on an object at which the entire weight of the body seemingly acts

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Moment

Back 16

It is the turning effect of a force

Front 17

Torque of a couple

Back 17

The turning effect caused by two equal and opposite forces whose lines of action do not coincide

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The principle of moments

Back 18

The sum of the clockwise moments taken about any point is equal to the sum of the anti-clockwise moments taken about the same point when a system is in equilibrium

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Energy

Back 19

Stored ability to do work

Front 20

Impulse

Back 20

It is the product of a force and the time during which the force is applied

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Work

Back 21

The product of a force and the distance moved in the direction of the force

Front 22

Power

Back 22

Rate of doing work

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Efficiency

Back 23

The fraction of the useful power output obtained from the total power input

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Density

Back 24

Mass per unit volume

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Crystalline

Back 25

The arrangement of the particles in the material are arranged in a regular 3-D lattice with well-defined structures visible

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Amorphous

Back 26

(without form) No regular repeating structure of particles in the material

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Polymeric

Back 27

Composed of long regular molecule chains and cross linking of these chains

Can undergo great strain and deform to a very great degree

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Ductile

Back 28

Undergo plastic deformation after considerable elastic deformation

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Brittle

Back 29

Does not exhibit any plastic deformation before breaking

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Ultimate tensile strength

Back 30

The maximum value of stress a material can withstand before breaking

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Pressure

Back 31

Perpendicular force per unit area

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Stress

Back 32

Perpendicular force per unit area

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Strain

Back 33

Extension per unit length

Front 34

Strain energy

Back 34

The energy stored in a body due to a change in shape

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Young's modulus

Back 35

Ratio of stress to strain - constant of proportionality

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Elastic deformation

Back 36

Temporary distortion-material returns to it's original shape on removal of the distorting force

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Plastic deformation

Back 37

When a small increase in stress causes a large increase in the strain

Front 38

Stress vs strain graphs (gradient and area under)

Back 38

Gradient=Young's modulus

Area=Work done or energy

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Electric field

Back 39

Region of space where electric charge experiences a force

Front 40

Electric current

Back 40

Rate of flow of charged particles

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Ampere

Back 41

1 coulomb per second passing through an electrical component

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Potential difference

Back 42

Energy converted from electrical to other forms of energy when unit charge passed through it

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Volt

Back 43

The p.d. between 2 points in which one joule of energy is converted when one coulomb of charge passes

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Resistance

Back 44

Ratio of p.d. to current

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Ohm

Back 45

One volt per ampere

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Resistivity

Back 46

The resistance between opposite faces of a cute of the material, of unit length and unit cross sectional area

Front 47

Coulomb

Back 47

1 coulomb is the amount of charge required to maintain a current of one ampere

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Ohm's law

Back 48

The current through a conductor is proportional to the p.d. across it provided that it's temperature remains constant

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Thermistor

Back 49

A specific type of resistor, as temperature increases, resistance decreases

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Electromotive force (e.m.f.)

Back 50

Energy converted to electrical energy per unit charge

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Kirchhoff's first law

Back 51

The algebraic sum of the current at a junction is zero

Related to the conservation of charge

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Kirchhoff's second law

Back 52

Around any closed loop in a circuit, the algebraic sum of the e.m.fs is equal to the algebraic sum of the p.ds

Related to the conservation of energy