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Question 1959

The brain of any computer system is:

AALU

BMemory

CControl unit

DCPU

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D. CPUThe CPU (Central Processing Unit) is known as the brain of the computer. It performs all major operations such as processing data, executing instructions, and controlling other components. The CPU consists of two main parts — the Arithmetic Logic Unit (ALU) for calculations and the Control Unit (CU) for directing operations. ALU: Handles arithmetic and logic operations only.Memory: Stores data and instructions, but doesn’t process them.Control Unit: Directs the flow of data but works as part of the CPU.

Question 1895

ATM means:

AAll Time Money

BAutomatic Teller Machine

CAutomated Teller Machine

DAny Time Money

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C. Automated Teller MachineATM stands for Automated Teller Machine. It is an electronic banking device that allows customers to perform financial transactions such as cash withdrawals, deposits, fund transfers, and balance inquiries without the need for a human teller. All Time/Any Time Money: Common informal phrases, not the actual full form.Automatic Teller Machine: Incorrect; the correct term is Automated, not Automatic.

Question 1894

Which of the following is the best conductor of heat ?

Amercury

Bsilver

Cleather

Dbenzene

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B. silverSilver is the best conductor of heat among the given options. It efficiently transfers heat due to the presence of free electrons that move easily within its metallic structure. Because of this property, silver is used in high-quality thermal equipment and electrical contacts. Mercury: A metal but conducts heat less effectively than silver.Leather and Benzene: Poor conductors of heat (insulators).

Question 1893

Glaciers always melt first at the:

Atop surface

Bsides

Cbottom

Dmiddle surface

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C. bottomGlaciers usually melt first at the bottom. The pressure at the base of a glacier is very high, which lowers the melting point of ice — a phenomenon known as pressure melting. Additionally, heat from the Earth’s crust and friction caused by glacier movement also contribute to faster melting at the base. Top surface: Exposed to air but melts slower due to lower pressure.Sides and middle surface: Experience less pressure and friction, so melting is slower.

Question 1892

Which among the following is the major cause of acid rain ?

ACarbon dioxide

BCarbon monoxide

COxygen

DNitrogen dioxide

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D. Nitrogen dioxideNitrogen dioxide (NO₂) is a major cause of acid rain. When released into the atmosphere from vehicle exhausts and industrial emissions, it reacts with water vapor to form nitric acid (HNO₃). Along with sulfur dioxide forming sulfuric acid, it contributes to acid rain, which damages vegetation, aquatic life, and buildings. Carbon dioxide: Causes global warming, not acid rain.Carbon monoxide: A toxic gas but not acidic.Oxygen: Essential for respiration, not a pollutant.

Question 1880

Which one of the following colours has longest wave length ?

AGreen

BYellow

CRed

DBlue

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C. RedRed light has the longest wavelength among visible colours, approximately 620–750 nanometers. Due to its longer wavelength, red light is scattered the least, which is why it is used in traffic signals and as warning lights for better visibility over long distances. Blue and Green: Shorter wavelengths, scattered more easily.Yellow: Intermediate wavelength between red and green.

Question 1843

The inert gas which is substituted for nitrogen in the air used by deep sea divers for breathing, is:

AArgon

BXenon

CHelium

DKrypton

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C. HeliumHelium is used instead of nitrogen in the breathing mixture for deep-sea divers. At high pressures underwater, nitrogen can dissolve in blood and cause nitrogen narcosis or “rapture of the deep.” Helium, being inert and less soluble in blood, prevents this condition and makes breathing easier under pressure. Argon, Xenon, Krypton: Inert gases but not suitable due to higher density and narcotic effects.

Question 1842

Which of the following allow the electric current to pass through it ?

AGlasses

BGraphite

CRubber

DPVC

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B. GraphiteGraphite allows electric current to pass through it. Although it is a form of carbon, its atoms are arranged in layers with free-moving electrons, making it a good conductor of electricity. This property makes graphite useful in electrodes, batteries, and brushes of electric motors. Glass, Rubber, PVC: All are insulators and do not conduct electricity.

Question 1840

Which of the following blood group is considered as Universal Donor ?

BAB

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D. OThe O blood group, specifically O negative (O−), is considered the Universal Donor because it can be safely transfused to people of all other blood groups. This is due to the absence of A and B antigens on red blood cells, minimizing the risk of immune reactions during transfusion. A: Can donate only to A and AB groups.AB: Universal recipient, not donor.B: Can donate only to B and AB groups.

Question 1839

Which of the following is used in pencils ?

AGraphite

BSilicon

CCharcoal

DPhosphorous

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A. GraphiteGraphite is used in pencils. It is a soft form of carbon that leaves a dark mark on paper due to its layered structure, where carbon atoms are arranged in sheets that slide easily over each other. Though commonly called “lead,” pencils actually contain graphite mixed with clay to adjust hardness. Silicon: Used in electronics, not pencils.Charcoal: Used in art drawing but not regular pencils.Phosphorous: Used in safety matches and fertilizers, not pencils.

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Science

The brain of any computer system is:

ATM means:

Which of the following is the best conductor of heat ?

Glaciers always melt first at the:

Which among the following is the major cause of acid rain ?

Which one of the following colours has longest wave length ?

The inert gas which is substituted for nitrogen in the air used by deep sea divers for breathing, is:

Which of the following allow the electric current to pass through it ?

Which of the following blood group is considered as Universal Donor ?

Which of the following is used in pencils ?

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