RRB NTPC 2014 PYQs

Question 1

Burning of fossil fuels causes

Accepted Answer

Burning fossil fuels releases sulfur impurities, leading to sulfur dioxide pollution, a major cause of acid rain and respiratory issues.

Question 2

A seller sells an article for ₹550 and gains 10%. At what price must he sell the article to gain 25%?

Accepted Answer

First, find the cost price (CP) using the 10% gain on ₹550. Then, calculate the new selling price (SP) by adding 25% profit to this CP.

Question 3

150 liters of a mixture of milk and water contains 74% milk. What amount of milk should be further added to make it a mixture containing 90% milk?

Accepted Answer

Initial milk is 74% of 150L = 111L. Water is 39L. Let 'x' be milk added. New milk is (111+x) and total is (150+x). Set (111+x)/(150+x) = 0.90 and solve for x.

Question 4

What does hard copy signify?

Accepted Answer

A hard copy refers to a physical printout of data, typically produced by a printer. It's a tangible form of information.

Question 5

Gypsum rock is formed from

Accepted Answer

Gypsum is an evaporite mineral, meaning it forms from the evaporation of saline water. This process leads to the chemical precipitation of minerals, classifying it as a chemically precipitated sedimentary rock.

Question 6

If X women can finish a job in Y days, then in how many days will 8 women finish the same job?

Accepted Answer

The total work is X * Y units. If 8 women do the same work, the number of days will be (Total Work) / (Number of Women), which is (XY)/8.

Question 7

RADAR stands for

Accepted Answer

RADAR is an acronym for Radio Detection And Ranging. It is a system that uses radio waves to detect and determine the range, angle, or velocity of objects.

Question 8

Which two rivers form the world’s largest delta?

Accepted Answer

The Ganges and Brahmaputra rivers merge to form the Sundarbans Delta, which is recognized as the world's largest delta system.

Question 9

Which of the following will replace ‘?’ in the series given below?2, 9, 28, 65, ?, 217, 344, 513

Accepted Answer

The series follows the pattern n³ + 1. For n=1, 1³+1=2; for n=2, 2³+1=9; for n=3, 3³+1=28; for n=4, 4³+1=65. Thus, for n=5, 5³+1 = 125+1 = 126.

Question 10

Functional activities of a cell are controlled by

Accepted Answer

The nucleus is often called the 'control center' of the cell because it contains the genetic material (DNA) and regulates all cellular activities.

Question 11

Which of the following numbers is similar to 1, 9 and 64?

Accepted Answer

The given numbers are 1 (1² or 1³), 9 (3²), and 64 (8² or 4³). The pattern is perfect squares or cubes. Option 3, 81, is a perfect square (9²).

Question 12

Hydrometer is used to measure _______.

Accepted Answer

A hydrometer is specifically designed to measure the specific gravity of liquids, which indicates their density relative to water.

Question 13

Which of the following has the highest thermal conductivity?

Accepted Answer

Diamond possesses the highest thermal conductivity among all known materials, significantly surpassing metals like copper, steel, and aluminium due to its strong covalent bonds.

Question 14

3.5×3.5−1.9×1.93.5×3.5+1.9×1.9=?

Accepted Answer

Recognize the expression as (a² - b²) / (a² + b²). Substitute a=3.5 and b=1.9. Calculate a²=12.25, b²=3.61. Then (12.25 - 3.61) / (12.25 + 3.61) = 8.64 / 15.86 = 0.544766... which rounds to 0.544793.

Question 15

Ram left his house for office at 5 km/h and reached 10 minutes earlier. Had he travelled at 4 km/h, he would have been 5 minutes late. What is the distance between Ram’s house and office?

Accepted Answer

Let distance be D. Time difference is 10 min early + 5 min late = 15 min = 1/4 hour. Equation: D/4 - D/5 = 1/4. Solving for D gives D = 5 km.

Question 16

Uranium enrichment is costly because

Accepted Answer

Uranium enrichment separates uranium-235 from uranium-238, both isotopes of uranium. This process is complex and energy-intensive due to their similar chemical properties.

Question 17

The leakage of which of the following gases caused the Bhopal gas tragedy?

Accepted Answer

The Bhopal gas tragedy, one of the world's worst industrial disasters, was caused by the leakage of Methyl Isocyanate (MIC) gas from the Union Carbide plant.

Question 18

A grocer fools his customers by using a weight of 900 gram instead of 1 kg. If he sells at the cost price, what is his profit percentage?

Accepted Answer

The grocer sells 900g but charges for 1000g. Profit is (1000-900)/900 * 100 = 100/900 * 100 = 11.11%.

Question 19

In which year did Delhi become the capital of India?

Accepted Answer

Delhi officially became the capital of British India in 1911, shifting from Calcutta. This decision was announced during the Delhi Durbar.

Question 20

The Mars Orbiter Mission entered the orbit of Mars on

Accepted Answer

The Mars Orbiter Mission, also known as Mangalyaan, successfully entered Mars' orbit on September 24, 2014, making India the first Asian nation to do so.