.................. is the loss of energy as the signal propagates outward, where the amount of energy depends on the frequency.
Noise
Delay distortion
Attenuation distortion
Dispersion
Correct Answer :
C. Attenuation distortion
Related Questions
Which of the following is the unit of signaling speed or modulation rate or the rate of symbol transmission?
Data rate
Bit rate
Signal to Noise Ratio
Baud rate
Which of the following aggregate function doesnt ignore NULLs in its results?
COUNT
COUNT(*)
MAX
none of these
In two-phase locking
the data items are locked in growing phase.
the data items are released in shrinking phase.
Both A and B are true
Both A and B are false
Aggregate functions are also called
serial functions
non-serial functions
row functions
column functions
In the architecture of a database system external level is the
physical level.
logical level.
conceptual level
view level.
DECLARE is a(an)
executable statement.
declarative statement.
Ordered file
none of the above
Which of the following is not a database object?
index
sequence
cursor
trigger
The statement
Every foreign-key value must match a primary-key value in an associated table
Is related to
View
Cursor defination
Referential intergrity
Trigger
Object based data models are used in describing the abstraction of the following levels?
Conceptual and view
Only physical
Physical and conceptual
Only conceptual
An association of several structure of a data base can be expressed graphically by?
Tuple
Record
Relationship
Field
A transaction is said to have terminated if it has
either committed or aborted
either partially committed or aborted
either committed or failed
none of these
In RDBMS, Data is presented as a collection of
Relation
Table
Attribute
Entity
Usenet is also known as
Newsgroups
10Km to 1Km
10^3Km to 100Km
100M to 10M
Which of the following extracts its data from the result of an SQL SELECT statement.
View
Synonym
Sequence
Transaction
Count function in SQL returns the number of
values.
distinct values.
groups.
columns.
Extended Entity Relationship model consists of which of the following
i) Specialization
ii) Generalization
iii) Categorization
i and ii only
ii and iii only
i and iii only
All i, ii iii
Secondary storage
magnetic disk
magnetic tape
juke box
cache
In an object oriented model, one object can access data of another object by passing?
Instance variable
Variable
Message
Function
Which of the following is not a constraint on a single relation?
check
unique
not null
is duplicate
A relation which is in 3NF is
in 1NF also
in 2NF also
free from transitive dependencies
All of these
By default a user who has been granted some form of authorization
is allowed to pass them to others
is not allowed to pass them to others
may be or may not be allowed to pass them to others
none
In E-R Diagram weak entity set are represented by
Ellipse
Dashed ellipse
Dashed Rectangle
Doubled Rectangle
Which of the following is not an Aggregate function?
Min
Max
Select
Avg
A logical schema
is the entire database.
is a standard way of organizing information into accessible parts.
describes how data is actually stored on disk.
both A) and C)
The privilege lists include
i) select
ii) insert
iii) update
iv) delete
only i)
only i) ii)
only i) ii) iii)
i) ii) iii) iv)
Natural mask for a Class A network
255.0.0.0
255.255.0.0
255.255.255.0
none of these
Which of the following is logical topology?
Bus
Ring
Star
None of these
Mail services are available to network users through the
Session layer
Presentation layer
Application layer
Transport layer
Technique(s) used for data recovery after any failure
Logging
Recovery manager
Both A and B are true
Both A and B are false
Data Manipulation Language DML) is not to
Create information table in the Database
Insertion of new information into the Database
Deletion of information in the Database
Modification of information in the Database