Questions

Q:

What are the different Adder circuits you studied?

Answer

Adders are generally of five types:


1.Ripple Carry Adder:


The Ripple carry adder(RCA) consists of a building block named Half Adder(HA) which is cascaded to form a Full Adder(FA). These buildingblocks HAs and FAs are also the building blocks of all types of adders.The n full adders are cascaded to form n bit RCA.


The full adder has three input pins(input Ai,input Bi,carryin Ci) and two output pins(Sum and Ci+1).Its equations are:


Sum=Ai^Bi^Ci


Ci+1=Ai.Bi+Bi.Ci+Ai.Ci


 


2. Carry Lookahead Adder:


The Carry Lookahead Adder(CLA) reduces the delay as that in RCA. Let Gi=Ai.Bi, and Pi=Ai^Bi, then Ci+1=Gi+Pi.Ci.


The expressions for Sum and Ci+1 is then defined completely in terms of input pins rather wait for input carry to appear.


 


3. Carry Select Adder:


The carry select adder uses duplicate modules for each combination of input carry(i.e. 1 and 0).The multiplexers then select the appropriate sum and carry output according to the carry output of the preceding stages.


 


4. Carry Skip Adder:


The carry skip adder are as fast as carry lookahead adders which are the fastest adders but its spped decreases to about 20-30% if input operands are 64-bit or more. In these adders we divide the input bit stream into various blocks and make use of two observations:


-if each element of the two bit streams are unequal,i.e. Ai!=Bi than the carry input of the block is equal to the carry input.


-if each element of the two bit streams are equal,i.e. Ai=Bi than the carry input of the block is opposite of the carry input.


 


5. Carry Save Adder:


The carry save adder reduces the addition of three elements into addition of two elements,i.e. if you want sum of nine numbers it reduces it into sum of six numbers. In first step the sum of three numbers is calculated without bothering for the carry.During the second step only carry is calculated which is then added to the generated sum to give the required sum. 

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Q:

Which article of the Indian Constitution deals with the creation of All India Services?

A) 315 B) 313
C) 312 D) 311
 
Answer & Explanation Answer: C) 312

Explanation:

312-Article of the Indian Constitution deals with the creation of All India Services.

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Q:

Nav Mangalore port located on the bank of which river?

A) Gurupura B) Sharavati
C) Kaveri D) Kumaradhara
 
Answer & Explanation Answer: A) Gurupura

Explanation:

Panambur is the site of seaport called Nav Mangalore port or New Mangalore Port. It is located to the north of the Gurupura river confluence with the Arabian Sea.

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Filed Under: Indian Geography
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Q:

Which of the following is used to preserve specimens in the biology laboratory?

A) Phenol B) Benzaldehyde
C) Formaldehyde D) Acetic acid
 
Answer & Explanation Answer: C) Formaldehyde

Explanation:

A 40% solution of Formaldehyde known as Formalin is used in the preservation of biological specimens because of its hardening action on proteins. 

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Filed Under: Chemistry

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Q:

How long is a giraffe tongue in feet

A) 1.6 B) 6
C) 18 D) 10
 
Answer & Explanation Answer: A) 1.6

Explanation:

A typical giraffe neck can stretch as long as six feet, the giraffe's tongue usually measures 18-20 inches long.

 

Why that much long:


Giraffe's eat Acacia tree leaves. The acacia tree's tasty leaves are protected by very sharp thorns. The giraffe's long tongue allows it to reach the highest, tastiest leaves while avoiding the sharp thorns. Its tongue also features a thick, tough layer that protects it from being cut by the thorns. If a giraffe's tongue does get cut by a thorn, its extra-thick saliva has antiseptic properties that help it to heal quickly.

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Q:

Who was the first Indian woman who owns the gold medal in Asian Games?

A) P.T.Usha B) Sunita Rani
C) Shiny Abraham D) Kamaljit Sandhu
 
Answer & Explanation Answer: D) Kamaljit Sandhu

Explanation:
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Q:

Who is the author of the book A Journey ?

A) Tony Blair B) Bikram seth
C) Janardhan takur D) harisen
 
Answer & Explanation Answer: A) Tony Blair

Explanation:

Author of the book A journey  is Tony Blair

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Q:

Tap water is placed in an open pad and allowed to evaporate. After some time the temperature of water 

A) increases to a great extent B) increases slightly
C) decreases slightly D) decreases rapidly
 
Answer & Explanation Answer: C) decreases slightly

Explanation:

Evaporation causing cooling.Here the evaporation is less. Therefore cooling is less.

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