NEET Foundation

NEET Chemistry Chapter 1 Matter In Our Surrounding Question And Answers

Question 1. Why does the aroma of coffee spread very fast?
Answer:

The gases have very fast rate of diffusion and therefore, the aroma of coffee spread very fast.

Question 2. Which property of gas is used in supplying oxygen cylinders to hospitals?
Answer:

Due to high compressibility of gases, oxygen cylinders are supplied to hospitals.

Question 3. What is common among the three states of matter? Why do the states of matter differ?
Answer:

The common thing among all the states of matter is that they all are made up of tiny particles which can be atoms, molecules or ions. The states of matter differ in the motion of these particles and the spaces they have in between.

Question 4. Separate the following substances in groups of high and low intermolecular force. Ice, Sulphur vapour, Nitrogen, Sugar, Copper, Air, Salt and Plastic.
Answer:

1. High Intermolecular Force: Ice, Sugar, Copper, Salt, Plastic
2. Low Intermolecular Forces: Sulphur vapour, Nitrogen, Air

Question 5. What do you understand by Brownian motion?
Answer:

Brownian motion

Brownian motion is the random movement of particles suspended in a fluid (liquid or gas) resulting from their collision with the fast-moving atoms or molecules in the gas or liquid.

Question 6. What is the reason of leaving a small gap at the joint of two rails?
Answer:

Reason behind the leaving a small gap at the joint of two rails is 

With increase in temperature any matter will expand as heat moves the particle apart. So with increase in heat the rail track also expands. If the gap is not kept the rails will bend due to expansion making the track unusable.

Question 7. What is dry ice?
Answer:

Dry ice

When carbon dioxide is turned into solid at high pressure, it is called dry ice.

Question 8. Under what conditions can the gases be liquified? In which form is LPG filled in a gas cylinder?
Answer:

By increasing the pressure, gases can be liquified. LPG is packed into cylinders in liquid state.

Question 9. Why to steam causes more severe burns?
Answer:

Steam causes more severe burns than boiling water because it has more heat energy than water due to its latent heat of vaporization.

Question 10. What are the factors that are responsible in bringing out the change in states of matter?
Answer”

Temperature and Pressure are the two factors which are responsible to bring out the change in the state of matter.

Question 11. The average body temperature of a man is 98.5 °F. What is this temperature in Celsius?
Answer:

The formula needed to convert Fahrenheit to Celsius is:

°C = \(\frac{5}{9}\left({ }^{\circ} \mathrm{F}-32\right)\)

Where °F and °C are the temperatures in Fahrenheit and Celsius respectively

Put 99.5 °F into the formula

°C = \(\frac{5}{9}(99.5-32)\)

°C = \(\frac{5}{9}(67.5)\)

°C = 37.5 °C

The average body temperature of a man in Celsius is 37.5 °C.

Question 12. What is the latent heat of vaporization of water?
Answer: The latent heat of vaporization of water is 22.5 × 105 Joules per kilogram

Question 13. What do you understand by specific latent heat?
Answer:

Specific latent heat

The heat energy required to boil or melt a substance is known as specific latent heat of that substance.

Question 14. What is latent heat of vaporization?
Answer:

Latent heat of vaporization

The amount of heat energy that is required to change 1 kg of solid into liquid at atmospheric pressure at its melting point is called latent heat of vaporization.

Question 15. What do you understand by evaporation?
Answer:

Evaporation

It is a phenomenon of changing liquid into vapour at any temperature below its boiling point, i.e., water changes from a liquid to a gas or vapour form.

Question 16. What is latent heat?
Answer:

Latent heat

When the water is vaporised from the surface, it needs energy to convert from a liquid state to a gaseous state. The water absorbs this heat energy from the environment. This energy does not heat the water but is used in converting from liquid to gas. This heat is called Latent heat.

NEET Chemistry Chapter 2 Is Matter Around Us Question And Answers

Question 1. Air is an example of a mixture. (True/False)
Answer. True

Question 2. Arrange true solution, suspension and colloid in the decreasing order of size of the particles.
Answer. Suspension > Colloids > Solution

Question 3. Smoke and fog both are aerosols. In what way are they different?
Answer. Smoke is Solid in gas type aerosol whereas, Fog is liquid in gas type aerosol.

Question 4. How does increasing the temperature of a solid affect its solubility? Is it same for the gases?
Answer. Solubility of a solid in a liquid increase with temperature whereas, for gases it decreases with an increase in temperature.

Question 5. What is an emulsion?
Answer.

Emulsion

A colloidal solution in which dispersing medium and dispersed phase both are liquid is called emulsion.

Question 6. Give a day-to-day example of Tyndall effect?
Answer. Tyndall Effect can be seen when headlight beams are visible on foggy nights.

Question 7. When will we choose fractional distillation instead of simple distillation process?
Answer. If we want to separate a mixture of two or more miscible liquids whose difference in boiling points is more than 25 K, then fractional distillation process is used.

Question 8. What is the principle of centrifugation?
Answer.

Principle of centrifugation

Centrifugation is based on the principle that when the solution is spun rapidly, then the denser particles will settle at the bottom and lighter particles will float on the top.

Question 9. What is miscibility?
Answer.

Miscibility

Miscibility refers to the ability of a liquid to completely dissolve in another liquid.

Question 10. In crystallization, the liquid left behind after the crystals are formed is called ___________. 
Answer. Mother liquor

Question 11. Evaporation is better than crystallization. (True/ False)
Answer. False

Question 12. We can separate miscible liquids using a separating funnel. (True/False)
Answer. False

NEET Biology Chapter 1 The Fundamental Unit Of Life Question And Answers

Question 1. Who discovered cells and how?
Answer:

Discovery Of Cell:

Cell was discovered by Robert Hooke in 1665 while studying a thin slice of cork through a crude microscope. He observed that cork resembled the structure of a honeycomb having many small compartments. These compartments were later known as cells.

Question 2. Why cell is called the structural and functional unit of life?
Answer: Cells are called the structural and functional unit of life because all living organisms are made up of cells. These cells carried out specific functions which is important for life processes.

Question 3. Write the main postulates of cell theory. Who propounded the cell theory?
Answer:

Rudolf Virchow propounded the concept of cell theory and gave the idea that all cells arise from pre-existing cells.

The main postulates of the modern cell theory are as follows.

• All organisms are made up of one or more cells and cell products.
• All metabolic reactions occur in cells. Hence, cells are structural and functional units of life.
• All cells arise from pre-existing cells, as an animal gives birth only to an animal and a plant gives rise only to a plant.
• An organism begins its life as a single cell.

Question 4. Differentiate between prokaryotic and eukaryotic cells.
Answer:

Difference between prokaryotic and eukaryotic cells

Question 5. What is chromatin?
Answer:

Chromatin

The chromatin is a thin, thread-like entangled mass of chromosome material and it consists of the genetic material DNA and proteins (i.e., histones). The chromatin is formed of repeating subunits called nucleosomes.

Question 6. What is plasmodesmata?
Answer:

Plasmodesmata

Cell wall consists of narrow pores known as pits through which very fine strands of cytoplasm known as plasmodesmata.

Question 7. Which organelle is known as the powerhouse of the cell and why?
Answer: Mitochondria is known as the powerhouse of cells because the energy required for various chemical activities needed to support life is released by mitochondria in the form of ATP (Adenosine triphosphate) molecules.

Question 8. Where do the lipids and proteins constituting the cell membrane gets synthesized?
Answer: Lipids are synthesized in smooth endoplasmic reticulum and the proteins are synthesized in endoplasmic reticulum.

Question 9. What are nuclear pores?
Answer:

Nuclear pores

The nuclear envelope makes the nucleus distinct from cytoplasm. It also contains many pores called nuclear pores and it consists of the liquid ground substance called nucleoplasm.

Question 10. What are the functions of nucleus?
Answer:

The functions of nucleus are

• Nucleus controls all metabolic activity of the cell.
• Nucleus regulates the cell cycle.
• Nucleus controls the transmission of hereditary characteristics from the parent to offspring.

Question 11. Name the following.

(a) Outer most layer of the cell wall connecting the two adjoining cells.

(b) Cell membrane is chemically made up of

(c) Fold of plasma membrane in bacterial cells.

(d) Component which is considered as dynamic part of cell.

(e) What happens to cell when placed in salt solution?

(f) Who proposed fluid mosaic model?

Answer: (a) Middle lamella (b) protein (c) mesosomes (d) nucleus (e) cell swells (f) S. J. Singer and G. L. Nicolson (1972)

Question 12. Define phagocytosis.
Answer:

Phagocytosis

Intake of solid material by evagination of cell membrane on the periphery is known as phagocytosis.

Question 13. Define active transport.
Answer:

Active transport

Active transport is a speedy process. Diffusion is a slow process. This transport can move substances through a biological membrane against the concentration gradient and it is unidirectional in nature.

Question 14. Define exocytosis.
Answer:

Exocytosis

Exocytosis is the process by which the intracellular vesicles in the cytoplasm fuse with the plasma membrane and release their contents into the surrounding medium.

Question 15. Differentiate between diffusion and osmosis.
Answer:

Difference between diffusion and osmosis

NEET Physics Chapter 5 Sound Multiple Choice Questions

Question 1. A note is a sound

1. Of a mixture of several frequencies
2. Of a mixture of two frequencies only
3. Of a single-frequency
4. Always unpleasant to listen

Answer. 3. of a single frequency

Question 2. A key of a mechanical piano struck gently and then struck again but much harder this time. In the second case

1. The sound will be louder but the pitch will not be different
2. The sound will be louder and the pitch will also be higher
3. The sound will be louder but the pitch will be lower
4. Both loudness and pitch will remain unaffected

Answer. 1. The sound will be louder but the pitch will not be different

Question 3. In SONAR, we use

1. Ultrasonic waves
2. Infrasonic waves
3. Radio waves
4. Audible sound waves

Answer. 1. ultrasonic waves

Question 4. Sound travels in the air if

1. articles of medium travel from one place to another
2. There is no moisture in the atmosphere
3. Disturbance moves
4. Both particles as well as disturbance travel from one place to another.

Answer. 3. Disturbance moves

Question 5. When we change feeble sound to loud sound we increase its

1. Frequency
2. Amplitude
3. Velocity
4. Wavelength

Answer. 2. amplitude

Question 6. In the curve half the wavelength is

1. A B
2. B D
3. D E
4. A E

Answer. 2. B D

Question 7. Earthquake produces which kind of sound before the main shock wave begins

1. Ultrasound
2. Infrasound
3. Audible sound
4. None of the above

Answer. 2. infrasound

Question 8. Infrasound can be heard by

1. Dog
2. Bat
3. Rhinoceros
4. Human beings

Answer. 3. Rhinoceros

Question 9. Before playing the orchestra in a musical concert, a sitarist tries to adjust the tension and pluck the string suitably. By doing so, he is adjusting.

1. Intensity of sound only
2. Amplitude of sound only
3. The frequency of the sitar string with the frequency of other musical instruments
4. Loudness of sound

Answer. 3. frequency of the sitar string with the frequency of other musical instruments

Question 10. The vibrating part of a guitar is

1. Hand
2. Fulcrum
3. String
4. Chords

Answer. 3. String

Question 11. The simplest part of the ear is

1. Inner ear
2. Middle ear
3. Outer ear
4. Cerebellum

Answer. 3. Outer ear

Chapter 5 Sound NEET MCQ Practice PDF Download

Question 12. Heinrich Rudolf Hertz was born on 22 February 1857 in Germany. He was a German physicist. He was the first person who prove the existence of electromagnetic waves through his experiments. He laid the foundation for the future development of radio, telephone, telegraph, and television.

He also discovered the photoelectric effect when he noticed that the charged object loses its charge quickly when illuminated by ultraviolet radiation. It was later explained by Albert Einstein.

He also started experimenting with cathode rays. He discovered that cathode rays can penetrate in thin\ metal foil. He developed a version of a cathode tube and worked on X-rays of ­different materials. But he never practically worked on actual 0020X rays.

The S.I. unit of frequency was named Hertz in his honor.

1. What is the S.I. unit of frequency?

1. Hertz
2. Metre
3. Second
4. m/s

Answer. 1. Hertz

2. When was Hertz born?

1. 15 March, 1857
2. 22 February, 1857
3. 22 February, 1859
4. 19 November, 1882

Answer. 2. 22 February, 1857

3. In which city was Hertz born?

1. London
2. Germany
3. Indonesia
4. America

Answer. 2. Germany

4. Hertz was the first person to introduce ______.

1. Electromagnetic waves
2. Magnetic waves
3. Electricity
4. Gas

Answer. 1. Electromagnetic waves

5. What was the full name of Hertz?

1. Henry Hertz
2. Rudolf Hertz
3. Heinrich Hertz
4. Heinrich Rudolf Hertz

Answer. 4. Heinrich Rudolf Hertz

Gravitation Chapter NEET Physics Questions PDF download

Question 1. Why do planets revolve around the sun?
Answer:

Planets revolve around the sun:

The planet revolve around the sun and not straight into it is because of gravitational motion.

Question 2. What is Universal law of gravitation?
Answer:

Universal law of gravitation:

According to Newton, the gravitational force acting between two bodies is directly proportional to the product of their masses and inversely proportional to the square of distance between their centres.

Question 3. Define gravitational constant.
Answer:

Gravitational constant:

Gravitational Constant ‘G’ is numerically equal to the gravitational force of attraction between two masses, each of mass 1 kg placed at a distance of 1 m.

Physics Gravitation NEET previous year questions

Question 4. Describe the importance of Universal law of gravitation.
Answer:

The importance of Universal law of gravitation:

Universal law of gravitation is important because it is:

The force that binds us to the earth.

The motion of moon around earth.

The motion of planets around the Sun.

The tides due to moon and sun.

Question 5. A Saturn year is 29.5 times the earth year. How far is Saturn from the sun (M) if the earth is 1.5 × 10⁸ km away from the sun?
Answer:

Given:

A Saturn year is 29.5 times the earth year.

it is given that

T_S = 29.5 T_e

R_e = 1.5 × 10¹¹ m

Now, according to Kepler’s third law

T_S²/T_e² = R_s³/R_e³

R_S = R_e (T_S/T_e)^2/3 = 1.5 × 10¹¹ ((29.5T_e)/T_e)^2/3

= 1.43 × 10¹² m

= 1.43 × 10⁹ km

NEET Physics Gravitation problems with step-by-step solution

Question 6. Define centre of gravity.
Answer:

Centre of gravity:

Each particle or portion of a body exp

eriences the force of gravity. The net effect of all these forces is equivalent to the effect of a single force mg acting through a point called centre of gravity of the body.

Question 7. A sphere of mass 40 kg is attached by a second sphere of mass 15 kg when their centres are 20 cm  apart, with a force of 0.1 milligram weight. Calculate the value of gravitational constant.
Answer:

Given:

A sphere of mass 40 kg is attached by a second sphere of mass 15 kg when their centres are 20 cm  apart, with a force of 0.1 milligram weight.

Here, m₁ = 40 kg, m₂ = 15 kg

R = 20 cm = 20/100 m = 2 × 10^-1 m

F = 0.1 milligram weight = 0.1 × 10^-3 gram weight

F = 10^-4 × 10^-3 kg wt

F = 10^-7 × 9.8 N (1 kg wt = 9.8 N)

F = \(G \frac{m_1 m_2}{r^2}\)

G = \(\frac{F \times r^2}{m_1 \times m_2}\)

G = 10^-7 × 9.8 × (2 × 10^-1)²/(40 × 15)

G = 6.53 × 10^-11 N m² kg^-2

Question 8. Find the gravitational force between the two protons kept at a separation of 1  femtometer (1 femtometre = 10^-15 m). The mass of a proton is 1.67 × 10^-27 kg.
Answer:

Gravitational force is given by:

F = \(G \frac{m_1 m_2}{r^2}\)

= (6.67 × 10^-11 Nm² kg^-2) × (1.67 × 10^-27 kg)²/(10^-15 m)²

= 1.86 × 10^-34 N

Question 9. Define acceleration due to gravity. Write its symbol and its value.
Answer:

Acceleration due to gravity:

The rate at which the velocity of a freely falling object increases is called acceleration due to gravity. It is denoted by g and its value is 9.8 m/s2.

Question 10. What is the relationship between acceleration due to gravity (g) and Universal gravitational constant?
Answer:

Relationship between acceleration due to gravity (g) and Universal gravitational constant

Acceleration due to gravity (g) is given by

g = GM/R²

Where M = mass of the planet

R = radius of the planet

Question 11. Define weight. Write its SI unit.
Answer:

Weight:

Weight of an object is the force with which earth attracts it towards its centre. SI unit of weight is Newton.

Question 12. The mass of an object is 120 kg on the surface of the earth. What would be its weight when  measured on the surface of the moon? What would be its mass on moon? (Take g = 10 m/s²)
Answer:

Given:

The mass of an object is 120 kg on the surface of the earth.

Mass of an object on the earth, m_e = 120 kg

Acceleration due to gravity on the earth, g_e = 10 m/s²

Weight of the object on the earth, We = ?

W_e = m_e × g_e

By putting the value we get,

W_e = 120 kg × 10 ms^-2

W_e = 1200 N

We know that the weight on the surface of moon is = (1/6) × its weight on the earth

W_e = 1/6 × 1200 N

W_e = 200 N

Question 13. An artificial satellite is moving in a circular orbit around the earth with a speed equal to half the  magnitude of escape velocity from the earth.

1. Determine the height of satellite above the earth’s surface.
2. If satellite is stopped suddenly in the orbit and allowed to fall freely to the earth, find the speed  with which it hits the surface of the earth.
   Radius of earth = 6.4 × 10⁶ m

Answer:

(1) Let M be the mass of the earth and R be its radius then escape velocity of earth is given by the equation

ve = \(\sqrt{\frac{2 G M}{R}}\)

For satellite of mass m and orbital radius r = R + h where h is the height of the satellite above the earth’s surface moving with speed v, we thus have

v = \(\sqrt{\frac{G M}{(R+h)}}\)

or,

It is given that

v = \(\frac{v_t}{2}\)

From equation (1) and (2)

From this we calculate that R + h = 2R or h = R

(2) Total initial energy of the satellite at height h above the surface of earth is

E_i = K.E. at height h + PE at height h

E_i = \(=0-\frac{G M m}{(R+h)}=-\frac{G M m}{R+h}\)

As the satellite is stopped in its orbit, KE at height h = 0. Let be the speed with which the satellite hits the surface of the earth. The final energy at the surface of the earth is

E_f = K.E. at h = 0 + P.E. at h = 0 = \(\frac{m v^2}{2}-\frac{G M m}{R}\)

From principle of conservation of energy Ef = Ei i.e.,

From above equation we can calculate v0 which is

v₀ = \(\sqrt{G M / R}\)

Now acceleration due to gravity on the surface of earth is given by

g = \(\frac{G M}{R^2} \text { or } \frac{G M}{R}=g R\)

Putting this in equation (3) and calculating, we get

v₀ = 7.92 × 10³ m/s

Question 14. Define one Pascal.
Answer:

Pascal:

One Pascal is the pressure experienced by the surface when 1 N force acts on 1 m2 area of the body.

Question 15. Give characteristics of pressure inside fluids.
Answer:

Characteristics of pressure inside fluids:

A fluid contained in a vessel at the same level exerts equal pressure in all directions and on the walls of the container.

Question 16. What are the factors affecting the pressure at a point in a liquid?
Answer:

The pressure at a point inside the liquid depends on the following factors:

• Depth of the point below the free surface.
• Density of liquid
• Acceleration due to gravity.

Question 17. Describe the laws of liquid pressure.
Answer:

The various laws of liquid pressure are:

• Pressure at a point inside liquid increases with depth from the free surface.
• In a stationary liquid, pressure is same at all point in a horizontal plane.
• Pressure is same in all directions about a point in liquid.
• Pressure at same depth is different in different liquids. It increases with increase in density of the liquid.

Question 18. What do you mean by the term buoyancy?
Answer:

Buoyancy:

When an object is partially or completely immersed in a liquid an upward force acts on it. This upward force is known as buoyancy.

Question 19. A solid body of mass 150 g and volume 250 cm³ is put in water. Will the body float or sink?
Answer:

Here, mass of the body, M = 150 g

Volume of body, V = 250 cm³

Density of body,

Since the density of the body is less than the density of water which is 1 g/cm3 the body will float on water.

Question 20. What do you mean by Archimedes’ principle?
Answer:

Archimedes’ Principle:

When an object is immersed in a liquid partially or completely, it experiences an upthrust which is equal to the weight of the liquid displaced by it.

Question 21. State 2 uses of Archimedes’ principle.
Answer:

The uses of Archimedes’ principle are:

• It is used in designing submarines and ships.
• It is used in lactometers, which is used to determine the purity of milk.

The mass of an empty bucket of capacity 10 litres is 1 kg. Find its mass when ­completely filled with a liquid relative density 0.8.

Answer:

Here, mass of empty bucket,

m = 1 kg

Volume of bucket,

V = 10 litres = 10 × 10^-3 m³ = 10^-2m³

Relative density of liquid,

R.D. = 0.8

R.D. = density of liquid/density of water

0.8 = d/1000 kg/m³

d = 0.8 × 1000 kg/m³

d = 800 kg/m³

Mass of liquid in bucket,

M = V × d

M = (10^-2m³) × (800 kg/m³)

M = 8 kg

Total mass in bucket = m + M = 1 kg + 8 kg = 9 kg

Question 22. A ball is thrown vertically upwards and rises to a height of 10 m. Calculate the velocity with which the object was thrown upwards.
Answer. 14 m/s

Question 23. What is the magnitude of the gravitational force between the earth and a 1 kg object kept on its surface? (Mass of the earth is 6 × 10²⁴ kg and radius of the earth is 6.4 × 10⁶ m).
Answer. 10N

Question 24. Gravitational force on the surface of the moon is only as strong as gravitational force on the earth. What is the weight in Newton of a 10 kg object on the moon and on the earth?
Answer. Weight of body on earth = 100N, Weight of body on moon = 17N

Question 25. A stone is thrown vertically upward with an initial velocity of 40 m/s. Taking g = 10 m/s², find the maximum height reached by the stone. What is the net displacement and the total distance covered by the stone?
Answer. Height = 80m, Total distance travelled = 160m, Total displacement = 0

Question 26. A ball thrown up vertically returns to the thrower after 6 s. Find (1) the velocity with which it was thrown up, (2) the maximum height it reaches, and (3) its position after 4 s.
Answer.

(1) Velocity = 30m/s

(2) 45m

(3) 40m above ground

NEET Physics Chapter 1 Motion Multiple Choice Questions

• Kinematics is the branch of classical mechanics. It includes motion of particles, objects and system of objects. It is mostly used in astrophysics, mechanical engineering, robotics, biomechanics. Astrophysics is the study of celestial bodies.
• Kinematic is a greek word derived from in which means to move.
• The word motion is described as any moving object with respect to time. It is described in terms of distance, displacement, time, speed, velocity and acceleration.
• If an object is still at a position, it is called stationary, rest, motionless or immobile. The quantity used to measure motion is called momentum. The momentum of object is related to mass and velocity of the object.

• Speed is a scalar quantity and velocity is a vector quantity. Velocity is described as the rate of change of position of an object with respect to time. Speed is the magnitude of the velocity of the object.

Solved Motion MCQs for NEET Physics

Question 1. Which of the following statements is ­correct?

1. Speed is a scalar quantity.
2. Velocity is a scalar quantity.
3. Displacement cannot be zero.
4. Kinematic is an English word.

Answer. 1. Speed is a scalar quantity.

Question 2. Which of the following subjects does not include kinematics?

1. Astrophysics
2. Mechanical engineering
3. Robotics
4. History

Answer. 4.

Question 3. A boy travels 15 km to north and returns back 8 km along the same path. What is its displacement in km?

1. 3
2. 5
3. 7
4. 9

Answer. 3. 7

Question 4. A boy travels 15 km in 5 mins. What is the speed of the boy in km/min?

1. 3
2. 5
3. 7
4. 9

Answer. 1. 3

Question 5. The velocity-time graph is a straight line parallel to time axis, when object is moving with a _______.

1. Uniform acceleration
2. Variable acceleration
3. Uniform Velocity
4. Variable Velocity

Answer. 3. Uniform Velocity

Solved Motion MCQs for NEET Physics

Question 6. Consider the following table where ­Column 2, 3 and 4 shows the distance travelled by object in each second.

Motion chapter MCQs for NEET preparation

Which object is moving with a constant speed?

1. Object 1
2. Object 2
3. Object 3
4. Objects 1 and 2

Answer. 1. Object 1

Question 7. Which one of the following is velocity-time relation?

1. v = u + at
2. S = ut + \(\frac{1}{2} a t^2\)
3. v² = u² + 2aS
4. None of the above

Answer. 1. v = u + at

Question 8. Which among the following is also called as negative acceleration?

1. Acceleration due to gravity
2. Retardation
3. Zero acceleration
4. Variable acceleration

Answer. 2. Retardation