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The correct answer is -Alpha ray.

Key Points

• Alpha Ray
• Alpha rays are positively charged particles consisting of two protons and two neutrons.
• They are produced through the decay of heavy, unstable atomic nuclei and are emitted in a narrow, straight path.
• They were first discovered in the late 19^th century by Ernest Rutherford.
• Alpha rays play a critical role in studying the nature of the atomic nucleus and nuclear physics.
• Alpha rays are produced during alpha decay when a nucleus has too many protons and too little binding energy to hold them together.
• The nucleus will emit an alpha particle, reducing the number of protons and increasing the stability of the atom.
• Alpha rays are highly ionizing.
• They can cause significant damage to living tissues if they come into direct contact.
• Alpha rays are very short-range, typically only traveling a few centimeters in the air.

Additional Information 

• Cathode Ray
• Cathode rays are negatively charged particles produced in a cathode ray tube.
• They are composed of electrons and are produced when an electric current is passed through a gas in the tube.
• Cathode rays have the ability to ionize gases and produce X-rays.
• They were first discovered in the late 19^th century by J.J. Thomson.
• The discovery of cathode rays led to the development of the electronic theory of matter.
• Beta Ray
• Beta rays are high-energy, high-speed electrons or positrons emitted by radioactive isotopes.
• They are produced through the decay of unstable atomic nuclei and are emitted in space.
• Beta rays can penetrate matter and cause ionization, harming living organisms.
• They were first discovered in the late 19^th century by Henri Becquerel.
• Beta rays play a critical role in the field of nuclear physics and nuclear medicine.

The correct option is keep the body moving along the circular path.

Key Points

Centripetal Force:

• Centripetal force is a force that acts on a body traveling in a circle and is aimed at the center of the body's motion.
• Its movement is orthogonal at a right angle to the body's motion in the direction of the body's path's center of curvature.
• It keeps the body moving along a circular path.

Additional Information

Centrifugal Force:

• The force experienced by an object traveling in a circle directed away from the center of the circle is known as Centrifugal Force.
• The force that pushes an item rotating away from its axis of rotation is known as centrifugal force.

The correct option is Kinetic energy to heat energy.

Key Points

• Energy transition entails Friction converting kinetic energy into heat energy.
• Friction between two surfaces causes kinetic energy from moving surfaces to be converted into thermal energy.
• The utilization of friction is produced by rubbing pieces of wood together to start a fire.

Additional Information

Kinetic Energy:

• The energy an object has as a result of motion is known as kinetic energy.

Heat Energy:

• The movement of tiny atoms, molecules, or ions in solids, liquids, and gases produces heat energy.
• Heat is the flow or transfer that occurs as a result of the temperature differential between two objects.

The correct option is bent towards left side.

Key Points

• A bus is moving along a straight path and takes a sharp turn to the right side suddenly. The passengers sitting on the bus will bend towards the left side.
• The lower portion of passengers closest to the bus tends to go in the direction of the sharp turn because of centripetal force, but the upper portion of passengers throws an outside centrifugal force.
• This is happening due to two forces that are acting at that time centripetal and centrifugal forces.

Additional Information

Centripetal Force:

• Centripetal force is a force that acts on a body traveling in a circle and is aimed at the center of the body's motion.
• Its movement is orthogonal at a right angle to the body's motion in the direction of the body's path's center of curvature.
• It keeps the body moving along a circular path.

Centrifugal Force:

• The force experienced by an object traveling in a circle directed away from the center of the circle is known as Centrifugal Force.
• The force that pushes an item rotating away from its axis of rotation is known as centrifugal force.

The correct option is the frequency of the sitar string with the frequency of other musical instruments.

Key Points

• Before playing the orchestra in a musical concert, a sitarist tries to adjust the tension and pluck the string suitably. By doing so, he/she is adjusting the frequency of the sitar string.

Additional Information

The frequency of the Sound:

• The number of times per second that a sound pressure wave repeats itself is known as frequency, often known as pitch.

The velocity of Sound:

• The distance that sound energy will travel through that material in a specific amount of time.
• It depends on the material's density, acoustic impedance, and temperature.

The amplitude of Sound:

• The height of a sound wave is quantified by its amplitude.
• The loudness or the maximum displacement of vibrating medium particles from their mean position at the time the sound is produced.

Wavelength of Sound:

• The distance separating two wave crests or troughs that occur consecutively.

The correct option is kerosene.

 Key Points

• A form of matter has no fixed shape but it has a fixed volume. An example of this form of matter is kerosene.
• The state of matter with a definite shape and volume is called solid.
• The state of matter which has no definite shape but has a definite or fixed volume is called liquid.
• The state of matter which has no definite shape and no definite volume is called gas.
• Kerosene is a substance that is present in a liquid state thus, it has a definite volume but no actual shape.

Additional Information

• Carbon Steel is a solid substance with a definite shape and volume.
• Krypton is a gaseous substance that has no definite shape or volume.

The correct option is Al₂O₃ and ZnO.

Key Points

• Some metal oxides react with acid as well as a base to produce salt and water. They are known as amphoteric oxides. Examples of amphoteric oxides are Al2O3 and ZnO.
• The oxides can act both as acidic and basic amphoteric oxides.
• Amphoteric oxides are also able to neutralize both acid and base.
• These oxides on mixing with water can produce an alkaline solution.
• Oxides like Al₂O₃, PbO, SnO, ZnO, etc. are amphoteric oxides.
• Example: Al₂O₃ in reaction with acid like hydrochloric acid can produce aluminum chloride i.e. salt and water.
• Al₂O₃(s) + 6HCl(aq) → 2AlCl₃(aq) + 3H₂O(l)
• ZnO in reaction with a base like sodium hydroxide can produce sodium zinc oxide and water.
• **ZnO(s) + 2NaOH(aq) → Na2ZnO2(aq) + H2O(l)**​

Additional Information

• ​CuO is the chemical formula of copper oxide. It is also known as cupric oxide.
• CuO is a basic oxide as on mixing with water it can produce copper hydroxide.
• Thus, CuO is not an amphoteric oxide.
• CuO is used as a nanoparticle.

The correct answer is More than one of the above.

Key Points

• Gases causing the greenhouse effect
• The greenhouse effect is a phenomenon where certain gases in the Earth's atmosphere trap heat from the sun and warm the planet.
• These gases are known as greenhouse gases and include
• carbon dioxide (CO₂),
• methane (CH₄),
• nitrous oxide (N₂O),
• fluorinated gases, and
• water vapour.
• Carbon dioxide (CO₂) and methane (CH₄) are two of the most significant greenhouse gases
• They are major gases that contribute to global warming.
• They trap heat in the atmosphere and prevent it from escaping into space.
• This heat trapping leads to an increase in global temperatures.
• The following activities produce large amounts of greenhouse gases
• burning of fossil fuels such as coal and oil produces large amounts of CO₂
• Agricultural practices and the digestive processes of livestock emit a significant amount of CH₄
• N₂O emissions include the burning of fossil fuels, industrial processes such as nitric acid production, and the degradation of organic matter in the soil.

The correct answer is CO₂.

Key Points

• Acid reaction with metal carbonates
• Acids react with metal carbonates to liberate carbon dioxide gas.
• The reaction occurs because
• the hydrogen ions from the acid react with the metal ions in the carbonate to form water, and
• the carbonate ion reacts with the hydrogen ion to form carbon dioxide.
• The balanced chemical equation for this reaction can be written as:
• Metal Carbonate + Acid → Salt + Carbon Dioxide + Water
• The carbonate ion reacts with the hydrogen ion to produce carbon dioxide gas and water.
• This reaction is exothermic.
• it releases heat energy and is a classic example of an acid-base reaction.
• The amount of carbon dioxide produced is proportional to the amount of acid used in the reaction.
• It can be measured by collecting the gas produced and weighing it.

The correct answer is -Oxalic acid.

Key Points

• Oxalic Acid:
• It has an empirical formula of C₂O₄H₂ or HOOCCOOH.
• It is a strong, dicarboxylic acid that is widely used as a cleaning agent, bleach and rust remover.
• It is also found in almost all living organism that uses Kreb's cycle.
• It can form highly toxic salts such as oxalates, which can cause kidney damage if ingested in large quantities.
• It is a colourless, crystalline solid that is soluble in water.

Additional Information

• Carbonic Acid:
• It is a weak, dibasic acid with the empirical formula of H₂CO₃
• It is naturally occurring in the human body and acts as a regulator of the body's pH levels
• It is produced in small amounts by the reaction between carbon dioxide and water
• It is found in many carbonated drinks, leading to its characteristic fizz
• It is widely used in the food and beverage industry as an acidulant, flavouring agent, and to maintain the pH of products.
• Acetic Acid:
• It is a colourless, volatile liquid with an empirical formula of C₂H₄O₂ or CH₃COOH.
• It is a key component of vinegar and is also used in producing many industrial chemicals, such as polyvinyl acetate and cellulose acetate.
• It is widely used as a preservative, flavouring agent and cleaning agent.
• It is a weak acid and has a sour, pungent taste.
• It is naturally produced in the human body in small amounts during the digestion of carbohydrates.