RRB JE GK Questions 2026

The work done against gravity is mgh = 40 × 10 × 5 = 2000 joule, and power is work divided by time, so 2000 ÷ 4 = 500 watt.

Platinum is the least reactive of the four, so it is found in nature in the free or native state as the metal itself.

Solder is an alloy of lead and tin, usually in nearly equal parts. An alloy is a mixture of a metal with one or more other elements, made to gain a property the pure metal lacks.

Absolute pressure is counted from the absolute zero of pressure, which is a perfect vacuum, so it can never be negative.

Hexadecimal is base sixteen, so the four places of C3B1 carry the weights 4096, 256, 16 and 1 from left to right, and the letters stand for numbers: A is 10, B is 11, C is 12, D is 13, E is 14 and F is 15.

Brakes work on friction: a lining is pressed against a moving drum or disc, and the rubbing force slows the wheel down.

Find each mass from F = ma, add the masses, then divide the same force by the total. The first block gives m1 = 5 ÷ 10 = 0.5 kg and the second gives m2 = 5 ÷ 20 = 0.25 kg.

The body is thrown up at 20 m/s and gravity takes away 10 m/s of speed every second, so after 2 seconds its speed is zero.

Boron has three electrons in its outermost shell, so it is a trivalent element and is used as a p-type dopant.

ABS stands for anti-lock braking system, a safety device that keeps the wheels from locking during hard braking.

A centre-tap full wave rectifier needs two p-n junction diodes, one for each half of the input cycle. The secondary winding of the transformer is tapped at its middle, so its two halves give equal voltages of opposite sign.

Kinetic energy depends on the square of the momentum, so the momentum grows as the square root of the energy.

A silicon diode in forward bias drops about 0.7 volt across itself, whatever the supply voltage is.

The ball falls from 10 m but rises back only 2.5 m, so it keeps one quarter of its energy and loses three quarters.

P waves, or primary waves, are longitudinal: the particles of the medium move back and forth along the same direction in which the wave travels, squeezing and stretching the rock like a sound wave.

Argon is a noble gas whose outer shell already holds eight electrons, so it has no room to take another one easily; adding an electron would mean starting a new shell, and energy has to be supplied rather than released.

Under the Bureau of Indian Standards specification for drinking water, IS 10500:2012, turbidity has an acceptable limit of 1 NTU and a maximum permissible limit of 5 NTU in the absence of any alternate source.

Leucoplasts are the colourless plastids of plant cells, and each kind is named after what it stores.

The same magnet moves at the same speed in both cases, so the rate of change of magnetic flux through the coil is equal and the induced potential difference has the same magnitude.

Producers, the green plants and algae, are the most numerous living part of an ecosystem because every other organism depends on them for food.