RRB JE CBT 1 2018-19 Exam has been started from today, so for last minute dose we are providing some important Science questions for RRB JE CBT 1 upcoming slots. As you all know that Science has high weightage in railway exams. So you should revise Science section very well.
Railway Ki Pathshala:RRB JE CBT 1 2018-19: General Science Quiz 5
The probability of these Science questions and topics is very high. So do practice these Science Questions and give a finishing touch to your preparation of Science section.
1. The force of attraction between an electron revolving around the nucleus and the nucleus is a _______force?
a) Mechanical
b) Electric
c) Magnetic
d) Gravitational
Ans. (b)
The force of attraction between an electron revolving around the nucleus and the nucleus is a electric force. As the nucleus is positively charged and surrounding is negatively charged, so as a resultant, they attract each other. As the nucleus is small, the force is very strong.
2. What are the components of nucleus of an atom?
a) Only Protons
b) Protons and Neutrons
c) Neutrons and Electrons
d) Only Neutrons
Ans. (b)
The main components in the nucleous of an atom are neutron and protons.
3. Why the clear nights are cooler than the cloudy nights?
a) Conductance
b) Condensation
c) Radiation
d) Insulation
Ans. (c)
In heat transfer by thermal radiation, the transfer is often between bodies, which may be separated spatially. Clouds act like blankets which prevent heat energy stored in the air and soil from leaving the Earth in the form of infrared radiation.
4. The first formed primary xylem elements are called ___________.
a) Metaxylem
b) Protoxylem
c) Xylem fibres
d) Xylem parenchyma
Ans. (b)
As a young vascular plant grows, one or more strands of primary xylem form in its stems and roots. The first xylem to develop is called ‘protoxylem’. In appearance protoxylem is usually distinguished by narrower vessels formed of smaller cells.
5. In humans, the sound is produced by the ________.
a) Oesophagus
b) Larynx
c) Medulla
d) Epiglottis
Ans. (b)
The larynx commonly called the voice box, is an organ in the neck of tetrapods involved in breathing, sound production, and protecting the trachea against food aspiration.
6. Lungs have a large number of alveoli for-
a) Having spongy texture and proper shape
b) More surface area for diffusion of gases
c) More space for increasing volume of inspired air
d) More nerve supply
Ans. (b)
The alveoli are tiny air sacs within the lungs where the exchange of oxygen and carbon dioxide takes place.
Gas exchange occurs only in alveoli.
There are so many alveoli within each alveolar sac and so many sacs at the end of each alveolar duct.
This produces a very large surface area that is available for gas exchange.
7. Oxide of which of the following will turn red litmus blue?
a) Magnesium
b) Phosphorus
c) Sulphur
d) Carbon
Ans. (a)
Oxides of metals are basic in nature hence they will turn red litmus to blue. Oxides of non-metals are acidic in nature hence they will turn blue litmus red. Magnesium is an oxide of a metal.
8. What is Brine solution?
a) Excess salt + water
b) Silver
c) Excess Ethanol + water
d) Excess starch + water
Ans. (a)
Brine is a high-concentration solution of salt in water. Brine is used as a preservative in meat-packing and pickling. Brine is also used to cool steel.
9. Chlorine gas is a major component of which of the following?
a) Water
b) Tear gas
c) Liquefied Petroleum Gas
d) Gobar gas
Ans. (b)
Tear Gas, also known as, lachrymator, is a chemical weapon that causes severe eye and respiratory pain, skin irritation, bleeding, and even blindness. It is made from a powdery compound called malononitrile and liquid solvent called methylene chloride.
It is mostly used in riot control.
10. Which of the following is CORRECT about Moon’s gravitation?
a) Moon’s gravitation = 1/6th of Earth’s gravitation
b) Moon’s gravitation =1/6th of Mars gravitation
c) Moon’s gravitation =1/8th of Earth’s gravitation
d) Moon’s gravitation = 1/8th of Mars gravitation
Ans. (a)
Moon’s gravitation is 1/6th of Earth’s gravitation. As G is a constant, know as the universal gravitational constant, which is equal to
6.67 × 10-11 m2 /kg2.
