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- Question 1 of 50
The instrument that measures and records the relative humidity of air is:
A hygrometer is an instrument used in meteorological science to measure the humidity, or amount of water vapour in the air.
- Question 2 of 50
The shape of our milky way galaxy is:
The shape of our milky way galaxy is spiral. The Milky Way is a huge collection of stars, dust and gas. It’s called a spiral galaxy because if you could view it from the top or bottom, it would look like a spinning pinwheel.
- Question 3 of 50
The different colours of different stars are due to the variation of:
Stars have different colors, which are indicators of temperature. The hottest stars tend to appear blue or blue-white, whereas the coolest stars are red.
- Question 4 of 50
The fundamental scientific principle in the operation of a battery is:
The fundamental scientific principle in the operation of a battery is dissociation of electrolytes. In dissociation of electrolytes, the addition of a solvent or of energy in the form of heat causes molecules or crystals of the substance to break up into ions (electrically charged particles).
- Question 5 of 50
Instrument used to measure the force and velocity of the wind is:
Anemometer is an instrument used to measure the force, pressure and velocity (speed) of the wind. It is an important tool for meteorologists, who study weather patterns.
- Question 6 of 50
Which combination of colours is the most convenient during day and night time?
White and black combination of colours is the most convenient during day and night time. Black text on a white background is best, since the color properties and light are best suited for the human eye. That’s because white reflects every wavelength in the color spectrum.
- Question 7 of 50
Woolen clothes keep the body warm because:
Woolen clothes keep the body warm because wool is a bad conductor of heat. Woolen clothes are thick and trap air inside forming a layer around the body and so it does not let our body temperature decrease through conduction.
- Question 8 of 50
If the length of a simple pendulum is halved then its period of oscillation is:
The time period of a pendulum is directly proportional to the square root of its length. So when its length is halved, its time period is decreased by a factor. If the length L of a simple pendulum is halved, then its period of oscillation will decrease by √2÷2.
- Question 9 of 50
Equilibrium is a condition that can:
In economics, economic equilibrium is a situation in which economic forces such as supply and demand (internal factors) are balanced and in the absence of external influences, the values of economic variables will not change.
- Question 10 of 50
While catching a ball, a player pulls down his hands to lower the:
By lowering his hands while catching the cricket ball, the player allows a longer time for momentum change (lower the momentum), thereby preventing his hands from getting injured.
- Question 11 of 50
Geostationary satellite revolves at:
Geostationary satellites orbit the earth at a fixed distance of 35,786 km. The speed of the satellite at this distance matches the earth’s rotation, thereby keeping the satellite stationary over a particular point on the earth.
- Question 12 of 50
When a barometer reading suddenly recedes, it indicates that climate:
A barometer measures air pressure. A rising barometer indicates increasing air pressure and a falling barometer indicates decreasing air pressure. When atmospheric pressure drops suddenly, this usually indicates that a storm is on its way.
- Question 13 of 50
A particle dropped from the top of a tower uniformly falls on ground at a distance which is equal to the height of tower. Which of the following paths will be traversed by the particle?
If an object moving forward in a straight line is affected by gravity it will fall in a parabolic arc. Since projectiles are objects affected only by gravity, the path of a projectile moving forward from the momentum of an initial thrust is parabolic.
- Question 14 of 50
Asteroids revolve around the Sun between which of the following two planets?
Asteroids are rocky objects revolving around the sun that are too small to be called planets. The asteroid belt is a torus-shaped region in the Solar System, located roughly between the orbits of the planets Mars and Jupiter.
- Question 15 of 50
Smog is a general pollutant where:
Smog is a kind of air pollution. The smoke usually came from large amounts of coal burning in an area and is caused by a mixture of smoke and sulfur dioxide (SO₂).
- Question 16 of 50
The speed of light with the rise in the temperature of the medium:
Temperature does not affect speed of light. Light is an electromagnetic wave and does not need any material medium to propagate.
- Question 17 of 50
Clothes keep us warm in winter because they:
Our body supplies the heat, and the clothes help to trap body heat and keeps the heat from escaping into the air. This is what keeps us warm.
- Question 18 of 50
In a refrigerator what produces the cooling?
The principle involved in a refrigerator is the rapid absorption of heat by the rapid evaporation of a volatile liquid. Refrigerators use a liquid that evaporates very easily, and this evaporation creates a cooling effect. They then compress the gas into a liquid again, and the whole process starts over.
- Question 19 of 50
Why are we able to hear short wave broadcasts better than long wave broadcasts?
Shorter waves move faster and have more energy, and longer waves travel more slowly and have less energy.
- Question 20 of 50
Electron microscope was invented by:
An electron microscope is a microscope that uses a beam of accelerated electrons as a source of illumination. It was invented by Ernst Ruska (physicist) and Max Knoll (electrical engineer), from the University of Berlin in 1931.
- Question 21 of 50
A passenger standing in a bus is thrown outward when the bus takes a sudden turn. This happens due to:
When a bus suddenly takes a turn the passengers are thrown outwards due to the property of inertia. As the passengers are still in their straight motion so they fall outwards.
- Question 22 of 50
Which of the following is not true for Geostationary Satellite?
A geostationary satellite is an earth-orbiting satellite, placed at an altitude of approximately 35,800 km directly over the equator, that revolves in the same direction the earth rotates (west to east). At this altitude, one orbit takes 24 hours, the same length of time as the earth requires to rotate once on its axis. So they seem stationary, relative to the Earth’s surface.
- Question 23 of 50
When pressure is increased the melting point of ice:
The melting point increases with an increase in pressure except for ice. The melting point of ice decreases when pressure increases. This strange behavior of the ice is observed because water expands when it freezes i.e. ice occupies more volume than liquid water.
- Question 24 of 50
Longitudinal waves cannot travel through:
Longitudinal waves such as sound cannot travel through the vacuum as they need a medium to travel. Light and other types of electromagnetic waves are considered transverse waves. These waves travel through a vacuum as they do not need a medium for their propagation.
- Question 25 of 50
Electrostatic precipitator is used to control the pollution of:
Electrostatic precipitator is used to control the pollution of air. It is a filterless device that removes fine particles, like dust and smoke, from a flowing gas using the force of an induced electrostatic charge minimally impeding the flow of gases through the unit.
- Question 26 of 50
When two ice cubes are pressed over each other they unite to form one cube, because of:
When the two ice cubes are pressed together, melting point of ice is lowered, so they melt to form a thin layer of water (between them). On releasing the pressure, the water formed freezes because decrease in pressure raises the freezing point. Hence they unite to form one cube. When water freezes, water molecules form a crystalline structure maintained by hydrogen bonding.
- Question 27 of 50
Which of the following parts of the sunlight makes the solar cooker hot?
In solar cookers, sunlight is converted to thermal energy. Infrared rays are responsible for the working of the solar cooker. Infrared radiation has the right energy to make the water, fat and protein molecules in food vibrate vigorously and heat up.
- Question 28 of 50
If the velocity-time graph of a particle is represented by y=mt+v, then the particle is moving with:
In this case the given equation shows that the velocity is linear with time and therefore the particle is moving with constant acceleration. If you travel with a constant acceleration, your velocity is always changing, but it’s changing by a consistent amount each second.
- Question 29 of 50
Which of the following occurred first?
Guglielmo Marconi sent out the first wireless signals in 1897. Max Planck unveiled the Quantum Theory in 1900. Wright Brothers successfully flew an aircraft in 1903. Albert Einstein propounded the General Theory of Relativity in 1915.
- Question 30 of 50
The animal which uses sounds as its ‘eyes’ is:
Bats navigate and find insect prey using echolocation. They produce ultrasound. The sound waves emitted by bats bounce off objects in their environment. Then, the sounds return to the bats’ ears, which are finely tuned to recognize their own unique calls.
- Question 31 of 50
The sky appears blue because of:
The sky appears blue to the human eye as the short waves of blue light are scattered more than the other colours in the spectrum, making the blue light more visible.
- Question 32 of 50
Dynamo is a device for converting:
A dynamo is a device for converting mechanical energy into electrical energy. In a dynamo, the mechanical energy of rotation is converted into electrical energy in the form of a current in the armature.
- Question 33 of 50
The working of the quartz crystal in the watch is based on:
The working of the quartz crystal in the watch is based on Piezoelectric effect. Piezoelectric Effect is the ability of certain materials to generate an electric charge in response to applied mechanical stress. A commonly known piezoelectric material is quartz.
- Question 34 of 50
Why does a big fire in the open appear to be fanned by strong winds?
When warm air (over the fire spot) rises, the air pressure at that place gets lowered. But around it, pressure is high so the air rushes from high-pressure zone to low-pressure zone giving an appearance of fanning the fire.
- Question 35 of 50
Oil rises up the wick in a lamp because:
Due to the presence of pores (narrow space) in the wick, capillary action takes place, which makes the oil rise in the wick. Capillary action is the process of a liquid flowing in a narrow space without the assistance of, or even in opposition to, any external forces like gravity.
- Question 36 of 50
In the atmosphere, ultraviolet rays are absorbed by:
Most of the ultraviolet radiation in sunlight is absorbed by oxygen in Earth’s atmosphere, which forms the ozone layer of the lower stratosphere.
- Question 37 of 50
In which of the following cryogenic engines are used?
A cryogenic rocket engine is a rocket engine that uses a cryogenic fuel and oxidizer; that is, both its fuel and oxidizer are gases which have been liquefied and are stored at very low temperatures.
- Question 38 of 50
Who propounded the possibility of placing communications satellites in geosynchronous orbit for the first time?
The concept was first proposed by Herman Potocnik in 1928 and popularised by the science fiction author Arthur C Clarke in a paper in Wireless World in 1945.
- Question 39 of 50
What was the name of the space shuttle that landed man on the moon?
Apollo 11 was the first manned mission to land on the Moon. The first steps by humans on another planetary body were taken by Neil Armstrong and Buzz Aldrin on July 20, 1969.
- Question 40 of 50
The energy emitted by the Sun is due to:
Nuclear Fusion reactions power the Sun and other stars. In a fusion reaction, two light nuclei merge to form a single heavier nucleus. The process releases energy because the total mass of the resulting single nucleus is less than the mass of the two original nuclei.
- Question 41 of 50
Tungsten is used for the manufacture of the filament of an electric bulb, because:
Tungsten metal is used exclusively for making the filament of electric bulbs because it has a very high melting point. Due to its high melting point, the tungsten filament can be kept white-hot without melting away.
- Question 42 of 50
What is the wavelength of visible spectrum?
The visible spectrum is the portion of the electromagnetic spectrum that is visible to the human eye. The wavelength of the Visible Light ranges between 380 nm to 750 nm (3800 to 7500 angstroms). (The limits of the visible spectrum are not sharply defined but vary among individuals)
- Question 43 of 50
Who invented Radar?
Robert Watson-Watt was a pioneer of radar technology. Although he did not invent the idea of radio detection, he was the first to prove it could work on a large scale. The world’s first true radar system was invented by an American electrical engineer Albert Hoyt Taylor and an American radio engineer Leo C Young.
- Question 44 of 50
Who measured the velocity of light first?
It was the Danish astronomer, Olaus Roemer, who, in 1676, first successfully measured the speed of light. His method was based on observations of the eclipses of the moons of Jupiter.
- Question 45 of 50
When a vehicle passes, TV reception gets distorted. This is because:
Many natural and man-made phenomena can disrupt the reception of television signals. These include naturally occurring and artificial spark discharges, and effects due to the operation of radio transmitters. TV reception gets distorted as spark plug creates electromagnetic disturbances.
- Question 46 of 50
Which of the following alloy is used in making magnet?
Alnico is a family of iron alloys which in addition to iron are composed primarily of aluminium (Al), nickel (Ni), and cobalt (Co), hence the acronym al-ni-co. They also include copper, and sometimes titanium. Alnico alloys are ferromagnetic, and are used to make permanent magnets.
- Question 47 of 50
Where are mesons found?
Mesons are hadronic subatomic particles composed of an equal number of quarks and antiquarks, usually one of each, bound together by strong interactions.
Outside the nucleus, mesons appear in nature only as short-lived products of very high-energy collisions between particles made of quarks, such as cosmic rays (high-energy protons and neutrons) and baryonic matter.
- Question 48 of 50
For a body moving with non-uniform velocity and uniform acceleration:
For a body moving with non-uniform velocity and uniform acceleration, Displacement–Time graph is nonlinear. Non-uniform motion occurs when an object’s velocity (either the magnitude, or the direction, or both) is variable (i.e. the object undergoes acceleration).
- Question 49 of 50
Lambert’s law is related to:
Lambert’s law is related to Illumination. This law stated that the loss of light intensity when it propagates in a medium is directly proportional to intensity and path length.
- Question 50 of 50
Which of the following laws validates the statement that matter can neither be created nor destroyed?
Law of conservation of mass validates the statement that matter can neither be created nor destroyed. Matter can change form through physical and chemical changes, but through any of these changes, matter is conserved. The same amount of matter exists before and after the change—none is created or destroyed.