RRB Group D GK Questions 2026

The great Bihar earthquake of 1934 destroyed the rail link across the Kosi between Nirmali and Saraigarh, and the river’s shifting course kept it broken for decades; the Kosi Rail Mahasetu, opened in 2020, restored the connection and cut the journey between Mithila and Kosi by hundreds of kilometres.

The Ganga waterway from Haldia to Prayagraj, declared in 1986 as the first national waterway of the country, is 1,620 kilometres long, and under the Jal Marg Vikas Project its channel was deepened and terminals were built, including the multimodal terminal at Patna.

National Waterway 1 follows the Ganga, the Bhagirathi and the Hooghly from Haldia in West Bengal up to Prayagraj, and a long stretch of it passes through Bihar by Buxar, Patna, Munger and Bhagalpur.

Vikramshila Setu, about four and a half kilometres long and opened in 2001, joins Bhagalpur on the south bank with Naugachhia on the north, and it takes its name from the ancient university of Vikramshila, whose ruins stand in the same district at Antichak.

The Mahatma Gandhi Setu, about 5.75 kilometres long and opened in 1982, runs from Patna to Hajipur in Vaishali district, the town that also holds the headquarters of the East Central Railway, and it is the main road link between the capital and north Bihar.

The bridge between Mokama and Simaria, opened in 1959 and inaugurated by Dr Rajendra Prasad, the first President of India, carried both a railway line and a road and was the first bridge of that kind over the Ganga anywhere in the country.

The East Central Railway, created in 2002 when the railways were reorganised into new zones, has its headquarters at Hajipur in Vaishali district, and it is the only zonal headquarters of the Indian Railways in Bihar.

A sphygmomanometer has an inflatable cuff wrapped around the upper arm, a rubber bulb to pump air into it, and a gauge, traditionally a column of mercury.

When an electric current is passed through brine, a concentrated aqueous solution of sodium chloride, the salt decomposes. Chlorine gas is given off at the anode and hydrogen gas at the cathode, while sodium hydroxide is left in the solution near the cathode.

RNA is usually single-stranded and its sugar, ribose, carries an extra hydroxyl group, which makes the molecule more reactive and easier to break or alter than double-stranded DNA.

By Newton's law of gravitation, the acceleration due to gravity at the surface is g = GM/R², where G is the universal gravitational constant, M is the mass of the Earth and R is its radius.

Molarity and molality are both standard ways of stating how much solute is present in a solution.

Torque is r into F into the sine of the angle between them, and since the force here is perpendicular to the rod the sine is one, so the torque is simply 0.5 multiplied by 20, that is 10 newton metre.

Varignon theorem states that the moment of a force about any point equals the algebraic sum of the moments of its components about the same point; it speaks of the moments themselves, not of their squares, so statement S1 is false as written.

Moment of inertia is the sum of each bit of mass multiplied by the square of its distance from the axis, so drawing the arms in reduces it.

A solid cone has more material near its wide base than near its apex, so its centre of gravity lies on the axis of symmetry well below the middle, at one quarter of the height measured from the base, which is three quarters of the height measured down from the…

In a wheelbarrow the wheel is the fulcrum, the load in the tray lies between the wheel and the hands, and the effort is applied at the handles, so the load sits in the middle, which defines a second class lever; a nutcracker, a bottle opener and a lemon squeezer…

In stable equilibrium the original position is the one of least potential energy, so a small displacement lifts the centre of gravity and the weight of the body brings it back, as with a cone resting on its base or a book lying flat on a table.

A zero net force gives translational equilibrium, so the body as a whole does not accelerate, and a zero net torque gives rotational equilibrium, so it does not begin to spin; complete equilibrium requires the two together.

Torque is the product of the force and the perpendicular distance of its line of action from the axis, so the same turning effect can be produced by a smaller force if that distance is made larger; a long handle therefore does the same work with less effort.