Physics Glossary

?
  • Created by: Abu2002
  • Created on: 05-01-19 14:08
Acceleration
Change of velocity per unit time
1 of 62
Acceleration of free fall
Acceleration of an object acted on only by the force of gravity
2 of 62
Accurate
A measurement that is obtained, using accurately-calibrated instruments correctly, is said to be accurate
3 of 62
Accuracy
A measurement is considered accurate if it is judged to be close to the true value
4 of 62
Base units
The units that define the SI system (e.g., the metre, the kilogram, the second, the ampere)
5 of 62
Breaking distance
The distance travelled by a vehicle in the time taken to stop it
6 of 62
Centre of mass
The centre of mass of a body is the point through which a single force on the body has no turning effect
7 of 62
Couple
Pair of equal and opposite forces acting on a body but not along the same line
8 of 62
Density of substance
Mass per unit volume of the substance
9 of 62
Displacement
Distance in a given direction
10 of 62
Drag force
The force of fluid resistance on an object moving through the fluid
11 of 62
Effort
The force applied to a machine to make it move
12 of 62
Elastic limit
Point beyond which a wire is permanently stretched
13 of 62
Elasticity
Property of a solid that enables it to regain its shape after it has been deformed or distorted
14 of 62
Energy
The capacity to do work
15 of 62
Equilibrium
State of an object when at rest or in uniform motion
16 of 62
Error bar
Representation of an uncertainty on a graph
17 of 62
Error of measurement
Difference between a measured value and the true value. Errors can include systematic (including zero error) and random
18 of 62
Force
Any interaction that can change the velocity of an object
19 of 62
Free body diagram
A diagram of an object showing only the forces acting on the object
20 of 62
Friction
Force opposing the motion of a surface that moves or tries to move across another surface
21 of 62
Gravitational field force
Force of gravity per unit mass on a small object
22 of 62
Hooke's law
The extension of a spring is proportional to the force needed to extend it
23 of 62
Inertia
Resistance of an object to change of its motion
24 of 62
Kinetic energy
The energy of an object due to its motion
25 of 62
Limit of proportionality
The limit beyond which, when a wire or a spring is stretched, its extension is no longer proportional to the force that stretches it
26 of 62
Linear
Two quantities are said to have a linear relationship if the change of one quantity is proportional to the change of the other
27 of 62
Load
The force to be overcome by a machine when it shifts or raises an object
28 of 62
Mass
Measure of the inertia or resistance to change of motion of an object
29 of 62
Moment of force about point
Force × perpendicular distance from the line of action of the force to the point
30 of 62
Momentum
mass × velocity
31 of 62
Newtons First
An object remains at rest or in uniform motion unless acted on by a resultant force
32 of 62
Newtons Second
The rate of change of momentum of an object is proportional to the resultant force (F) on it. Newton’s 2nd law may be written as F = (Δmv)/Δt. For constant mass, this equation becomes F = ma where acceleration a = (Δv/Δt)
33 of 62
Pascal
Unit of pressure or stress equal to 1 N m –2
34 of 62
Potential difference
Work done or energy transfer per unit charge between two points when charge moves from one point to the other
35 of 62
Potential energy
The energy of an object due to its position
36 of 62
Power
Rate of transfer of energy
37 of 62
Precision of a measurement
Precise measurements are ones in which there is very little spread about the mean value. Precision depends only on the extent of random error and it gives no indication of how close the results are to the true value
38 of 62
Precision of a instrument
The smallest non-zero reading that can be measured, also sometimes referred to as the instrument sensitivity or resolution
39 of 62
Pressure
Force per unit area acting on a surface perpendicular to the surface
40 of 62
Principle for the conservation of energy
Energy cannot be created or destroyed
41 of 62
Principle of moments
For an object in equilibrium, the sum of the clockwise moments about any point = the sum of the anticlockwise moments about that point
42 of 62
Probable error
Estimate of the uncertainty of a measurement
43 of 62
Projectile
A projected object in motion acted on only by the force of gravity
44 of 62
Random error
Error of measurement due to results varying in an unpredictable way from one measurement to the next. They cannot be corrected. The effect of random errors can be reduced by making more measurements and calculating a new mean
45 of 62
Range of a set of readings
The range of a set of readings of the same measurement is the difference between the minimum and the maximum reading
46 of 62
Range of an instrument
The difference between the minimum and the maximum reading that can be obtained using the instrument
47 of 62
Scalar
A physical quantity with magnitude only
48 of 62
Sensitivity of an instrument
The output reading per unit input quantity
49 of 62
SI system
The scientific system of units
50 of 62
Speed
Change of distance per unit time
51 of 62
Stopping distance
thinking distance + braking distance
52 of 62
Systematic error
Cause readings to differ from the true value by a consistent amount each time a measurement is made. Sources of systematic errors can include the environment, methods of observation, or instruments used
53 of 62
Terminal speed
The maximum speed reached by an object when the drag force on it is equal and opposite to the force causing the motion of the object
54 of 62
Thinking distance
The distance travelled by a vehicle in the time it takes the driver to react
55 of 62
Uncertainty
The interval within which the true value can be expected to lie, with a given level of confidence or probability
56 of 62
Useful energy
Energy transferred to where it is wanted when it is wanted
57 of 62
Vector
A physical quantity with magnitude and direction
58 of 62
Velocity
Change of displacement per unit time
59 of 62
Weight
The force of gravity acting on an object
60 of 62
Work
force × distance moved in the direction of the force
61 of 62
Zero Error
Any indication that a measuring system gives a false reading when the true value of a measured quantity is zero. A zero error may result in a systematic uncertainty
62 of 62

Other cards in this set

Card 2

Front

Acceleration of an object acted on only by the force of gravity

Back

Acceleration of free fall

Card 3

Front

A measurement that is obtained, using accurately-calibrated instruments correctly, is said to be accurate

Back

Preview of the back of card 3

Card 4

Front

A measurement is considered accurate if it is judged to be close to the true value

Back

Preview of the back of card 4

Card 5

Front

The units that define the SI system (e.g., the metre, the kilogram, the second, the ampere)

Back

Preview of the back of card 5
View more cards

Comments

No comments have yet been made

Similar Physics resources:

See all Physics resources »See all Mechanics resources »