RRB JE Electrical solved question paper 2014 | RRB JE Electrical

Answer.1. Our perspiration evaporates quickly

Explanation:-

Evaporation is a process by which a liquid changed into ^Yapour state at any temperature below its boiling point. Absorption of heat energy from thy surroundings makes the surroundings cool.

Thus, evaporation of a liquid is always accompanied by a decrease in temperature of the surroundings, i.e. Evaporation causes a cooling effect.

Applications of Cooling Caused by Evaporation

Let us take some examples of evaporation and the applications of the cooling effect caused by it.

1. During hot summer days, water is kept in earthenware pots (matkas) to keep it cool. These pots have a number of extremely small holes (pores) in their walls. When water is put in these pots, it comes in contact with surrounding air through these pores. Water particles absorb heat from the surrounding air and evaporate from the pores. This cools the pots and the remaining water.
2. If you put a small amount of acetone (nail polish remover) or rectified spirit or petrol on your palm, it evaporates very quickly. The liquid on the palm takes heat energy from the palm for its evaporations. This results in the cooling of your palm.
3. It is a common experience that we perspire on a hot sunny day or after doing physical exercises. In these situations, the body temperature increases causing our sweat glands to release sweat (water along with minerals and salts) from our skin. The water is released as sweat takes heat from the surroundings and evaporates making us feel cooler.
4. Why do we feel cool while sitting under a fan? When the fan circulates air the rate of evaporation of sweat from our body increases. The air from the fan blows away the water vapor formed during evaporation making us feel cooler.
5. We often sprinkle water on the open ground or the roof after a hot sunny day. This water absorbs heat from the surface of the earth or roof and evaporates. During this process, the surface of the earth or roof becomes cool.

Answer.3. Saprophytic

Explanation:-

Wastewater contains many billions of bacteria, and most of these are fecal bacteria. However, these bacteria, once outside their normal habitat (is when they are in the ‘extra-intestinal’ environment), are unable to survive for very long. This is because they are outcompeted by the large numbers of saprophytic bacteria which grow naturally and profusely in the nutrient-rich aquatic environment of a microbiological wastewater treatment reactor. These ‘saprophytes’ obtain their energy, cell carbon, and other essential nutrients from the organic and inorganic compounds in the wastewater. They are very well adapted to this environment, whereas the fecal bacteria are not- and so they die, some quickly and some more slowly.

Answer.4. Nucleus

Explanation:-

In cell biology, the nucleus is a membrane-enclosed organelle found in eukaryotic cells. Briefly, the nucleus contains large quantities of DNA, which are the genes. The genes determine the characteristics of the cell’s proteins, including the structural proteins, as well as the intracellular enzymes that control cytoplasmic and nuclear activities.

The genes within these chromosomes are the cell’s nuclear genome. The function of the nucleus is to maintain the integrity of these genes and to control the activities of the cell by regulating gene expression — the nucleus is, therefore, the control center of the cell.

Answer.2. Heart disease

Explanation:-

The procedure to unblock narrowed coronary arteries of the heart is known as coronary angioplasty. The doctor often performs this procedure immediately after the heart attack.

Answer.4. AIDS

Explanation:-

The Human Immunodeficiency Virus (HIV) is defined as a virus spread through certain body fluids that attack the body’s immune system.

Acquired immunodeficiency syndrome (AIDS) is caused by the Human Immunodeficiency Virus (HIV). HIV attacks the immune system. Therefore it destroys the body’s ability to fight infections and disease.

HIV is spread through certain body fluids blood, semen, vaginal fluids, rectal fluids, and breast milk. HIV is not spread by air, water, insects, casual contact (shaking hands, hugging, dancing, sharing dishes), closed mouth or social kissing, or toilet seats. It is not spread through saliva, tears, or sweat unless these body fluids contain HIV-infected blood.

Note:- Tuberculosis, Typhoid, and Tetanus are bacterial diseases.

Answer.3. Mesosome

Explanation:-

Mesosomes: They are vesicular, convoluted al multi-laminated structures formed as an invagination of the plasma membrane in the cytoplasm. They are prominent in Gram-positive bacteria. There are two types of mesosomes i.e septal mesosome and lateral mesosome. The septal mesosome it attached to the bacterial chromosome and is involved in DNA segregation and in the formation of cross walls during cell division. They are also called chondroid and are visualized only under an electron microscope. They are more prominent in some Gram-positive bacteria.

Functions

1. They are the sites of respiratory enzymes in bacteria.

2. Coordinate nuclear and cytoplasmic division during binary fission.

3. Responsible for compartments DNA at sporulation.

Answer.3. 2⁴ − 1

Explanation:-

Conversion of binary to decimal

(1111)₂ = 1 × 2³ + 1 × 2² + 1 × 2¹ + 1 ×2⁰

(1111)₂ = 8 + 4 + 2 + 1

(1111)₂ = (15)₁₀

15 = 2⁴ − 1

Answer.1. 400 J

Explanation:-

When an object (the system) halls from a particular height, fir where its gravitational potential energy is mgh with respect to the ground, the gravitational potential energy is transformed into kinetic energy. Neglecting losses due to friction and other sources, the loss in gravitational potential energy results in a gain in kinetic energy as the object accelerates toward the ground. The object’s gravitational potential energy will have been totally converted into kinetic energy the instant before the object strikes the ground. 

Kinetic energy = mgh J

m = 20

g = 10

h = 2

Kinetic energy = 20 × 10 × 2 = 400 Joule

Answer.3. Scavenging

Explanation:-

Scavenging is both a carnivorous and herbivorous feeding behavior in which individual scavengers search out the dead animal (corpses or carrion and dead plant biomass on which to feed. The eating of carrion from the same species is referred to as cannibalism. Scavengers play an important role in the ecosystem by contributing to the decomposition of dead animals and plant material. Decomposers and detritivores complete this process, by consuming the remains left by scavengers.

Answer.3. Natural siphon type

Explanation:-

Natural siphon type rain gauge:- This type of recording rain gauge is also known as float type gauge. Here the rainfall collected by a funnel-shaped collector is led into a float chamber causing a float to rise. As the float rises, a pen attached to the float through a lever system records the elevation of the float on a rotating drum driven by a clocks work mechanism. A siphon arrangement empties the float chamber when the float has reached a pre-set maximum level. This type of rain gauge is adopted as the standard recording-type rain gauge in India and its details are described in Indian Standard.