With reference to "water vapour", which of the following statements is/are correct? 1. It is a gas, the amount of which decreases with altitude. 2. Its percentage is maximum at the poles. Select the answer using the code given below:

Which one of the following is synthesised in human body that dilates blood vessels and increases blood flow?

In a pressure cooker, the temperature at which the food is cooked depends mainly upon which of the following? 1. Area of the hole in the lid. 2. Temperature of the flame 3. Weight of the lid. Select the correct answer using the code given below.

Bisphenol A (BPA), a cause of concern, is a structural/key component in the manufacture of which of the following kinds of plastics?

Triclosan considered harmful when exposed to high levels for a long time, is most likely present in which of the following?

Water can dissolve more substances than any other liquid because

With reference to street-lighting, how do sodium lamps differ from LED lamps? 1. Sodium lamps produce light in 360 degrees, but it is not so in the case of LED lamps. 2. As streetlights, sodium lamps have longer lifespan than LED lamps. 3. The spectrum of visible light from sodium lamps is almost monochromatic while LED lamps offer significant colour advantages in street lighting. Select the correct answer using the code given below:

Fruits stored in a cold chamber exhibit longer storage life because

Ball bearings are used in bicycles, cars, etc., because

The known forces of nature can be divided into four classes, viz., gravity, electromagnetism, weak nuclear force and strong nuclear force. With reference to them, which one of the following statements is not correct?

Consider the following statements: 1. Size of the sun at dusk 2. Colour of the sun at dawn 3. Moon being visible at dawn 4. Twinkle of stars in the sky 5. Polestar being visible in the sky — Which of the above are optical illusions?

The efforts to detect the existence of Higgs boson particle have become frequent news in the recent past. What is/are the importance/importance’s of discovering this particle? 1. It will enable us to understand as to why elementary particles have mass. 2. It will enable us in the near future to develop the technology of transferring matter from one point to another without traversing the physical space between them. 3. It will enable us to create better fuels for nuclear mission. Select the correct answer using the codes given below:

What is the difference between a CFL and an LED lamp? (a) To produce light, a CFL uses mercury vapor and phosphor while an LED lamp uses semi-conductor material. (b) The average life span of a CFL is much longer than that of an LED lamp. (c) A CFL is less energy efficient as compared to an LED lamp. Which of the statements given above is/are correct?

Match List I with List II and select the correct answerList I: A. Potassium bromide B. Potassium nitrate C. Potassium sulphate D. Monopotassium tartarate List II: 1. Fertiliser 2. Photography 3. Bakery 4. Gunpowder A B C D

Which one of the following metals does not form amalgams?

A fuse is used in main electric supply as a safety device. Which one of the following statements about the fuse is correct?

Consumption of fish is considered to be healthy when compared to flesh of other animals because fish contains

Assertion (A): Formic acid is a stronger acid than acetic acid. Reason (R): Formic acid is an organic acid.

Assertion (A): The temperature of a metal wire rises when an electric current is passed through it. Reason (R): Collision of metal atoms with each other releases heat energy.

Assertion (A): Sodium metal is stored under kerosene. Reason (R): Metallic sodium melts when exposed to air.

The complete conversion of glucose in the presence of oxygen into carbon dioxide and water with release of energy is called

Which one of the following is a vector quantity?

Which one of the following is an active component of oil of clove?

The most reactive among the halogens is

Alpha-keratin is a protein present in

Which one of the following is paramagnetic in nature?

Which one of the following has the highest fuel value?

The planet Mercury is revolving in an elliptical orbit around the sun as shown in the given figure. The kinetic energy of Mercury is greatest at the point labeled

Which one of the following is used as an anti-freeze for the automobile engines?

The working principle of a washing machine

When a mirror is rotated by an angle θ, the reflected ray will rotate by

When an air bubble at the bottom of lake rises to the top, it will

Living organisms require at least 27 elements of which 15 are metals. Among these, those required in major quantities include

Total internal reflection can take place when light travels from:

Physico-chemical characteristics of water in water sources undergo changes due to

When the frequency distribution is normal

The offending substance in the liquor tragedies leading to blindness etc. is

Besides proteins and carbohydrates, other elements of nutritional value found in milk include

Which one of the following elements is alloyed with iron to produce steel which can resist high temperatures and also have high hardness and abrasion resistance?

Fat present below the skin surface in our body, acts as a barrier against

Assertion (A) : A diamond sparkles more than a glass imitation cut to the same shape. Reason (R) : The refractive index of diamond is less than that of glass. In context of the above two statements, which one of the following is correct?

Who among the following anticipated Newton by declaring that all things gravitate to the earth?

Optical fiber works on the principle of

An air bubble in water will act like a

The technique used to transmit audio signals in television broadcasts is

Suppose a rocket ship is receding from the earth at a speed 2?10 of the velocity of light. A light in the rocket ship appears blue to the passengers on the ship. What colour would it appear to an observer on the earth?

The chemical used as a fixer in photography is

Which one of the following polymers is widely used for making bullet proof material?

The clouds float in the atmosphere because of their low

The variations in temperatures from 0° C to 100° C with respect to time of two liquids P, Q are shown in the graph given below: Which one of the following statements is correct?

The pitch of the voice of women is in general

In an electronic watch, the component corresponding to pendulum of a pendulum clock is a

One mole of hydrogen gas burns in excess of oxygen to give 290 kJ of heat. What is the amount of heat produced when 4g of hydrogen gas is burnt under the same conditions?

If a gas is compressed to half of its original volume at 27°C, to what temperature should it be heated to make it occupy its original volume?

Which one of the following combinations of aperture and shutter speed of a camera will allow the maximum exposure?

A corked bottle full of water when frozen will break because

The speed of light will be minimum while passing through

The acceleration due to gravity of a catastrophic earthquake will be

The colour of a star is an indication of its

The colour of an opaque object is due to the colour it

The basic reason for the extraordinary sparkle of a suitably cut diamond is that

The main constituents of pearl are

Galvanised iron sheets are protected from rusting due to the presence of a layer of

Water is a good solvent of ionic salts because

The Government of India has totally banned the export of ‘Burnt Coal’ (Jhama), because it contains recoverable amount of a metal/element used in transistors. Which one is the element?

When there is depletion of ozone in the stratosphere, the wavelength of radiation striking the earth’s surface will be

The working of the quartz crystal in the watch is based on the

The formation of brilliant colors in soap film is a consequence of the phenomenon of

At what temperature are the readings of a Centigrade and Fahrenheit thermometer the same?

Which one of the following colloidal systems is represented by fog?

Assertions (A) : A mixture of salt and ice gives temperature below 0°C. Reason (R) : The salt raises the freezing point of ice. In the context of the above two statements, which one of the following is correct?

Vinegar is an aqueous solution of

The blood pressure values of four persons are given below : 1. Mrs. X : 90/60 2. Mr. X : 160/120 3. Mr. Y : 120/80 4. Mrs. Y : 140/100 Who among the following has normal blood pressure?

The bats are able to fly in dark since their wings produce

Which one of the following is an element?

Which one of the following will take place when a watch based on oscillating spring is taken to a deep mine?

Match List I with List II and select the correct answer by using the codes given below the lists. List I A. Barometer B. Chronometer C. Sextant D. Quadrant List II 1. Used for measuring altitudes and angles in navigation and astronomy 2. Used for measurement of angular distances between two digits 3. Keeps very accurate time as the one that is used to determine longitude at sea 4. Used for measuring atmospheric pressure 5. An instrument used in the diagnosis of pregnancy A B C D

What is the increasing order of the wavelengths of the following colors? 1. Orange 2. Indigo 3. Yellow 4. Violet

Galvanising of sheet iron is done by dipping the sheet metal into molten

German silver is an alloy of

Gypsum is added to cement clinker to

The minimum possible temperature beyond which matter cannot be cooled is

Which of the following pairs of substances can be completely separated by sublimation?

A passing motorcycle causes distortion or disturbance with reception of signal in radio and T.V. The cause of this is

Assume that A denotes narrow wheel, A wider wheel, B denotes small freewheel, B larger freewheel, C denotes small gearwheel, C larger gearwheel, in a rural area where there are sandy tracts, it will be advisable to use a bicycle with

An instrument measures the voltage of 50 Hz sinusoidal current as 220 V. The mean average voltage of the sinusoidal current is

The chemical name of ‘Aspirin’ is

Soap was never actually discovered but instead gradually evolved from crude mixtures of alkaline and fatty material. Up to 1800, soap was believed to be a mechanical mixture of fat and alkali, then Chevreul, a French chemist showed that soap formation, was actually a chemical reaction. Which one of the following follows from the above statement?

The rainbow and the rainbow-like colors seen on a thin film of oil on a water surface are two phenomena. They are

Superconductors are so called because they

Given below are colors of the visible spectrum. Identify the correct sequence in order of Increasing wavelengths.

Assertion (A) : A tennis ball will bounce higher in Calcutta than it would in Shimla. Reason (R) : The downward pull due to gravity is less and air is more rarefied in Shimla than in Calcutta.

Assertion (A): When a ship moves from the sea water into fresh water of a river, the ship will relatively sink. Reason (R) : The density of sea water is higher than that of the fresh water.

Assertion (A): Unlike photographic film, which can be used only once, video tapes can be reused several times. Reason (R): Photography involves chemical change but video recording is a physical change.

The process of retting in jute is

Water which contains soluble salts of calcium and magnesium is known as

Assertion (A): When a wheel is in motion, a point (on the rim) which is farthest away from the ground will have the highest speed while the point (on the rim) closest to the ground will have the lowest speed. Reason (R): The speed of the point on the rim in the direction of motion and along the circumference of the wheel is additive.

Assertion (A): Activated charcoal is used for decolourising sugar solution. Reason (R): Activated charcoal absorbs the impurities on its surface.

The chemical name of ‘aspirin’ is

The distance between the two successive nodes of a standing wave is

A boat filled with some stones is floating in water. If the stones are dropped into the water, the level of the water will

Total internal reflection occurs when light travels from

Sparkling red colour after the blast of fire crackers is due to the presence of

A chair is tilted about two of its legs and then left. It would return to its original position if

Sodium vapour lamps are preferred to incandescent lamps because of

Which of the following is not an alloy?

Atmospheric pressure exerted on earth is due to the

A small weight put on the pressure cooker increases the pressure of steam because

Birds get thrust (forward motion) and lift (upward motion) from the

If camera A has f 4.5 lens and camera B has f 2.8 lens, and the diameters of both the lenses are equal, then

The Sri Lanka Broadcasting Corporation broadcasts its programmes on the 25 metre band. Which one of the following is the frequency of this transmission?

Balloon filled with air is weighed (W) so that it just floats in water as shown in the figure. When it is further pushed by a short distance in water, it will

The major ingredient of leather is

A free-floating astronaut ‘A’ pushes another free-floating astronaut ‘B’ in space. The mass of ‘A’ is greater than that of ‘B’. The force exerted by the astronaut ‘A’ on the astronaut ‘B’ will be

The phenomenon of mirage is due to

If there were no atmosphere, what would be the colour of sky?

Assertion (A): Detergents can easily remove oil and dirt from soiled garments. Reason (R): Detergents increase the surface tension of water.

Assertion (A): Red phosphorous is preferred to white phosphorous in the manufacture of matches. Reason (R): Red phosphorous is non-poisonous in nature.

Ice skating can be used to demonstrate that when ice is under pressure, its

Match the columns: List 1 – Organic acids List 2 – Substances in which they are present. A. Lactic acid 1. Lemon B. Acetic acid 2. Rancid butter C. Citric acid 3. Milk D. Butyric acid 4. Vinegar 5. Wine Select the correct answer from the codes given below: A B C D

The newly discovered high-temperature superconductors are

Ordinary dry air consists of the following: (1) Nitrogen (2) Oxygen (3) Argon (4) Carbon dioxide What is the decreasing sequence of these in percentages?

The resolving power of an electron microscope is much higher than that of an ordinary light microscope because resolving power increases

Which of the following groups of instruments is required to have communication line between two television relay centres?

Distribution of electric power from one place to another is done at high A.C. voltage because

Resistance of a 100 watt bulb is R1 and that of a 60 watt bulb is R2. Which of the following is correct ?

A man coming down on a lift leaves a ball from his hand. The ball will

Which of the following is the correct sequence in order of increasing power consumption?

A small wooden block is floating in a tub of water. The water is gradually heated. The volume of the wooden block visible above the water level

If a toy boat in a tank sinks, the level of water will

To increase the voltage of alternating current, we can use

In the given figure, if P is a point of the source of light, R is retina and L is the lens of the eye, the person having such condition of his eyes is suffering from

Which of the following statements is incorrect?

Assertion: Alkalies are used for washing utensils. Reason: Alkalies are readily soluble in water.

Ball bearings are used to reduce the friction by

Microphone is a device in which the

Study the frequency of the following electromagnetic radiations and select the correct relationship (‘>’ implies greater than): I.: Infrared II.: Microwave III.: Ultraviolet

Ice cubes are floating in a glass of water. When the ice cubes melt, the water level in the glass

Which of the following is correct for tea?

Match the columns: (A) Glass ? (1) Phosphorus (B) Match ? (2) Sodium chloride (C) Fertiliser ? (3) Sodium silicate (D) Salt ? (4) Potassium sulphate A B C D

Radio waves travel with a speed of

If the distance that a radio wave can travel in the time of one complete cycle is 10 metres, then the frequency of the radio wave in cycles per second is

The centre of gravity of the floating ship

Which of the following is not an alloy?

Chlorine is

Solution of washing soda in water is.

Why do you feel chill after having a dip in sea water?

The surface of the water in a lake is frozen and its temperature is -15°C. The maximum possible temperature of the water inside the lake in contact with the ice layer will be

A stone is tied to a rope and attached to a wooden bar which rotates at constant angular velocity. Suddenly the bar is stopped. The stone gets encircled around the bar. What happens to the angular velocity of the stone?

The tape of the tape-recorder is coated with

When a brick is dropped in water, bubbles are seen to rise. This is due to

Which of the following is a perception without stimuli?

A person sitting in a bus experiences a jerk, when the bus stops all of a sudden. This is due to

The internal antenna of a transistor set is made of

When one enters a dark room, he is not able to see anything but after some time his vision improves. This is because

Aspirin is a

Helium is used for respiration in deep water instead of nitrogen because

In a fluorescent tube which of the following components are found?

In a remote Indian village with a scarcity of fuel, the people draw water from a well. They should be advised before drinking that water to

Arrange the following in the decreasing order of their carbon content I. Cast iron II. Wrought iron III. Steel

Assertion: Galvanised iron pipes do not rust easily. Reason: Zinc has a higher rate of oxidation than iron.

The substance generally used in the tip of safety match stick is

The process by which metal surface is coated with thin layer of zinc is called

Kilowatt is the unit of

Which of the following is useful in the chemistry of photography

The dress made out of which of the following is safe to wear while cooking?

Diamond and Emerald contain

The rich source of iron is

A fan makes a hot noon to feel cool by

When a ship enters a sea from a river, its portion under water will

What happens when the temperature of water falls from 30°C and 0°C ?

Which of the following is commonly present in the acids?

Why does man weigh more at the poles than at the equator?

Why camphor disappears when kept on a plate?

Why is it easier to cook in a pressure cooker?

What are the primary colors?

If water contracts on freezing, which of the following would happen?

What is the function of a fuse wire?

Why is it advisable not to draw current for many appliances from a single point?

Range of Television Broadcasting is confined to a limited distance because

What type of mirror is used by motorists to see the road behind them?

In microphone, transformation of energy takes place from

The heater element in an electric iron is made of

Stainless steel contains which of the following?

When iron rusts, the weight

Municipal water in India is generally treated with

In India people suffer from Anaemia due to lack of

A body partially floats in water when

Permanent hardness of water cannot be removed by

In summer, man with excess perspiration feels weak, because of the

In high mountain regions bleeding through nose occurs because

One litre of cold air weighs heavier than the dry air (1 Lit) because of the

Different notes are produced by a flute by

Which of the following metals is used in the electromagnets?

A ball bounces higher at high altitudes than in plains. This is because

An ordinary clock loses time in summer. This is because

When light enters a closed room through a small hole in the door, the image of an outside building appears as inverted on the opposite wall. This is because

The water in an open pond remains cool even in hot summer because

If a large number of people are enclosed in a room, then