RRB JE GK Questions 2026

An ocean thermal energy conversion plant works only where the warm surface water is at least about 20 degrees Celsius hotter than the cold water drawn from the depths.

A body that slides down a smooth slope turns all of its potential energy mgh into translational kinetic energy and reaches the bottom with a speed equal to the square root of 2gh.

The force on a current carrying conductor kept in a magnetic field is given by F equal to B I L sin theta, where theta is the angle between the direction of the current and the direction of the field.

The law of conservation of linear momentum follows straight from Newton's second law: the rate of change of the momentum of a system equals the net external force acting on it, so when that force is zero the total momentum stays the same in size and in direction.

Dynamic viscosity measures how strongly a fluid resists flowing, and in the centimetre gram second system it is measured in poise, a unit named after the French physician Jean Louis Marie Poiseuille, who studied the flow of blood in narrow tubes.

One byte holds eight bits, and each bit can be either 0 or 1, so the number of different patterns is 2 raised to the power 8, that is 256.

Hexadecimal has base 16 and therefore needs sixteen different symbols. The digits 0 to 9 serve for the first ten values, and because no single digit exists for the values 10 to 15, the letters A to F are borrowed.

The 2's complement is found in two steps. First take the 1's complement by changing every 0 to 1 and every 1 to 0; for 1010 this gives 0101.

ASCII stands for American Standard Code for Information Interchange. In its standard form it is a seven-bit code, so it can represent 2 raised to the power 7, that is 128 different characters: the English capital and small letters, the ten digit symbols, punctuation marks and a set of control…

To convert a binary number to decimal, write the place values from the right as 1, 2, 4, 8, 16 and so on, multiply each bit by its place value and add the results.

The octal system has base 8, so it uses only the eight digits from 0 to 7. The general rule is that the largest digit of any number system is one less than its base, which means the digits 8 and 9 can never appear in an octal number.

Storage units in computing grow in powers of two rather than powers of ten, because addresses are binary. One kilobyte is 2 raised to the power 10 bytes, which equals 1024 bytes.

A bit, short for binary digit, is a single 0 or 1 and is the smallest unit of data a computer handles.

The safest way to handle a binary subtraction in an examination is to convert both numbers to decimal, subtract, and convert the answer back.

To turn a binary number into octal, group the bits in threes starting from the rightmost bit, adding leading zeros to complete the last group, because three bits cover the eight octal digits.

Octal has base 8, and because 2 raised to the power 3 equals 8, every octal digit expands into exactly three binary bits.

Hexadecimal has base 16, and because 2 raised to the power 4 equals 16, exactly four binary bits make one hexadecimal digit.

Hydrofluorocarbons were adopted as substitutes for chlorofluorocarbons in refrigeration and air conditioning because they do not harm the ozone layer, but they turned out to be very powerful greenhouse gases, so the Kigali Amendment of 2016 brought them under the Montreal Protocol with a schedule for reducing their use.

The day marks the signing of the Montreal Protocol on Substances that Deplete the Ozone Layer in 1987 and is observed every year with a theme announced by the United Nations.

Marble is calcium carbonate, and sulphur dioxide in polluted air, along with the sulphuric acid of acid rain, reacts with it to form calcium sulphate, so the stone loses its shine, turns yellow and becomes pitted and flaky.