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Saitama Public High School Entrance Examination - Science study materials
Saitama Public High School Entrance Examination - Science study resources

Saitama Public High School Entrance Examination - Science practice questions

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Question 1Physics: measurements, energy and circuits

Which unit is used to measure force in the SI system?

  1. newton (N) Correct answer.
  2. watt (W)
  3. pascal (Pa)
  4. joule (J)

Explanation

Force is measured in newtons (N). One newton is the force needed to accelerate a 1 kg mass at 1 m/s².

Question 2Physics: measurements, energy and circuits

An object moves at a constant velocity. Which statement about the net force on it is correct?

  1. The net force is in the direction of motion
  2. The net force is zero Correct answer.
  3. The net force increases with speed
  4. The net force is opposite to motion

Explanation

By Newton's first law, constant velocity means zero acceleration, so the net force on the object is zero.

Question 3Physics: measurements, energy and circuits

A book rests on a table. Which pair of forces is a true action-reaction pair under Newton's third law?

  1. The book's weight; the table's upward push on the book
  2. The table's weight; the floor's upward push on the table
  3. The book pushes down on the table; the table pushes up on the book Correct answer.
  4. The book's weight; the book's mass

Explanation

A third-law pair is two forces of equal size and opposite direction acting on two different bodies. The book pushing down on the table and the table pushing up on the book are exactly that pair.

Question 4Physics: measurements, energy and circuits

Which type of circuit has the same current flowing through every component?

  1. A series circuit Correct answer.
  2. A parallel circuit
  3. A circuit with a capacitor
  4. Any closed circuit

Explanation

In a series circuit there is only one path, so the same current flows through every component.

Question 5Physics: measurements, energy and circuits

A sound wave has a frequency of 500 Hz and a speed of 340 m/s. What is its wavelength?

  1. 2 m
  2. 170000 m
  3. 0.68 m Correct answer.
  4. 1.47 m

Explanation

Wave speed = frequency × wavelength, so wavelength = speed/frequency = 340/500 = 0.68 m.

Question 6Physics: measurements, energy and circuits

A ball is dropped and falls freely. Neglecting air resistance, as it falls its:

  1. potential energy decreases and kinetic energy increases Correct answer.
  2. both energies stay constant
  3. potential energy increases and kinetic energy decreases
  4. both energies decrease

Explanation

As the ball loses height, gravitational potential energy decreases; that energy converts into kinetic energy, so kinetic energy increases as it speeds up.

Question 7Physics: measurements, energy and circuits

A lever is used to lift a 300 N load with an effort of 60 N. If the effort arm is 1.5 m, what is the load arm? (Assume the lever is balanced.)

  1. 0.5 m
  2. 1.2 m
  3. 0.3 m Correct answer.
  4. 7.5 m

Explanation

For a balanced lever, effort × effort arm = load × load arm. So 60 × 1.5 = 300 × load arm, giving load arm = 90/300 = 0.3 m.

Question 8Physics: measurements, energy and circuits

Which statement about a concave (converging) lens is correct?

  1. It cannot form any image
  2. It always forms a real inverted image
  3. It diverges parallel rays and forms only virtual, upright images Correct answer.
  4. It converges parallel rays to a real focus

Explanation

A concave (diverging) lens spreads parallel rays and can only form virtual, upright, diminished images.

Question 9Physics: measurements, energy and circuits

A motor lifts a 50 N weight through 4 m in 10 s. What is its power output?

  1. 500 W
  2. 200 W
  3. 20 W Correct answer.
  4. 12.5 W

Explanation

Work = 50 × 4 = 200 J. Power = work/time = 200/10 = 20 W.

Question 10Physics: measurements, energy and circuits

A permanent magnet is brought near an unmagnetised iron nail. The nail becomes attracted because:

  1. magnetic domains in the nail align under the magnet's field Correct answer.
  2. the magnet transfers electrons to the nail
  3. gravity between them increases
  4. the nail gains a net electric charge

Explanation

The magnet's field aligns the randomly oriented magnetic domains in the iron, inducing opposite poles that attract.

Question 11Physics: measurements, energy and circuits

Three 12 ohm resistors are connected in parallel. What is the total resistance?

  1. 36 ohm
  2. 4 ohm Correct answer.
  3. 6 ohm
  4. 12 ohm

Explanation

For three equal resistors R in parallel, total = R/3 = 12/3 = 4 ohm.

Question 12Physics: measurements, energy and circuits

An object is placed 2 cm in front of a convex lens of focal length 5 cm. The image formed is:

  1. virtual, inverted and diminished
  2. real, inverted and diminished
  3. virtual, upright and magnified Correct answer.
  4. real, inverted and magnified

Explanation

Since the object is within the focal length (2 cm < 5 cm), a convex lens forms a virtual, upright, magnified image on the same side as the object.

Question 13Physics: measurements, energy and circuits

Which colour of visible light has the longest wavelength?

  1. Red Correct answer.
  2. Green
  3. Violet
  4. Blue

Explanation

In the visible spectrum, red has the longest wavelength and the lowest frequency, while violet has the shortest wavelength.

Question 14Physics: measurements, energy and circuits

A machine has an input work of 500 J and an output work of 400 J. The energy 'lost' (20% of the input) is mainly converted into:

  1. heat due to friction Correct answer.
  2. sound that does useful work
  3. mass
  4. chemical energy

Explanation

The 100 J difference is mostly dissipated as heat due to friction between moving parts, consistent with conservation of energy.

Question 15Physics: measurements, energy and circuits

A compass needle points roughly geographic north. This is because Earth has:

  1. a magnetic field whose south pole is near geographic north Correct answer.
  2. an electric field pointing north
  3. a permanent ice field affecting iron
  4. a strong gravitational field at the pole

Explanation

Earth acts like a magnet; its magnetic south pole is near geographic north, so the north-seeking end of the compass needle points toward it.

Question 16Chemistry: particles, reactions and mass

Which state of matter has a definite volume but no definite shape?

  1. Liquid Correct answer.
  2. Plasma
  3. Solid
  4. Gas

Explanation

A liquid has a fixed volume but takes the shape of its container, so it has no definite shape.

Question 17Chemistry: particles, reactions and mass

During evaporation, the temperature of the remaining liquid tends to:

  1. stay exactly the same
  2. decrease Correct answer.
  3. rise to boiling point
  4. increase

Explanation

The fastest (highest-energy) molecules leave the surface, so the average kinetic energy of the remaining liquid falls and its temperature decreases.

Question 18Chemistry: particles, reactions and mass

The atomic number of an element is determined by the number of:

  1. neutrons in the nucleus
  2. electrons in the outer shell
  3. protons plus neutrons
  4. protons in the nucleus Correct answer.

Explanation

The atomic number equals the number of protons in the nucleus, which defines the element.

Question 19Chemistry: particles, reactions and mass

Which substance is a compound?

  1. Iron (Fe)
  2. Gold (Au)
  3. Oxygen (O2)
  4. Water (H2O) Correct answer.

Explanation

Water contains two elements (hydrogen and oxygen) chemically combined, so it is a compound. The others are elements.

Question 20Chemistry: particles, reactions and mass

Balance the equation: H2 + O2 -> H2O. The correct coefficients are:

  1. 2, 1, 1
  2. 2, 2, 2
  3. 2, 1, 2 Correct answer.
  4. 1, 1, 1

Explanation

2H2 + O2 -> 2H2O balances hydrogen (4 on each side) and oxygen (2 on each side).

Question 21Chemistry: particles, reactions and mass

Which property describes an acid?

  1. It has a pH above 7
  2. It turns red litmus paper blue
  3. It turns blue litmus paper red Correct answer.
  4. It feels slippery on skin

Explanation

Acids have pH below 7 and turn blue litmus paper red. The other choices describe bases.

Question 22Chemistry: particles, reactions and mass

When hydrochloric acid reacts with sodium hydroxide, the products are sodium chloride and:

  1. carbon dioxide
  2. oxygen gas
  3. hydrogen gas
  4. water Correct answer.

Explanation

This is a neutralisation reaction: HCl + NaOH -> NaCl + H2O. The products are a salt and water.

Question 23Chemistry: particles, reactions and mass

Which is a chemical change rather than a physical change?

  1. Burning a piece of wood Correct answer.
  2. Boiling water
  3. Melting ice
  4. Dissolving salt in water

Explanation

Burning produces new substances (ash, carbon dioxide, water vapour) and is irreversible, so it is a chemical change. The others only change state or dissolve.

Question 24Chemistry: particles, reactions and mass

In the reaction Zn + 2HCl -> ZnCl2 + H2, how many grams of hydrogen are produced from 65 g of zinc? (Zn = 65, H = 1)

  1. 65 g
  2. 1 g
  3. 136 g
  4. 2 g Correct answer.

Explanation

65 g Zn is 1 mol of Zn, which produces 1 mol of H2. Molar mass of H2 = 2 × 1 = 2 g, so 2 g of hydrogen is produced.

Question 25Chemistry: particles, reactions and mass

Which gas is most abundant in Earth's atmosphere?

  1. Oxygen
  2. Nitrogen Correct answer.
  3. Carbon dioxide
  4. Argon

Explanation

Nitrogen makes up about 78% of the atmosphere, oxygen about 21%, and the rest are trace gases.

Question 26Chemistry: particles, reactions and mass

A candle burns in a closed jar and goes out. The main reason it stops burning is that:

  1. the jar runs out of fuel
  2. the oxygen in the jar is used up Correct answer.
  3. the carbon dioxide reaches the wick and cools it
  4. nitrogen prevents burning

Explanation

Burning requires oxygen. In a closed jar the limited oxygen is consumed and the flame is extinguished.

Question 27Chemistry: particles, reactions and mass

Limewater turns milky when carbon dioxide is bubbled through it because:

  1. insoluble calcium carbonate forms Correct answer.
  2. oxygen is released
  3. the gas dissolves to make the water cloudy
  4. the limewater evaporates

Explanation

CO2 reacts with calcium hydroxide to form insoluble calcium carbonate, which makes the limewater appear milky.

Question 28Chemistry: particles, reactions and mass

The law of conservation of mass in a chemical reaction means:

  1. the total mass of reactants equals the total mass of products Correct answer.
  2. atoms are destroyed and remade
  3. the number of molecules is unchanged
  4. mass can be created if energy is added

Explanation

In a closed system, atoms are rearranged but not created or destroyed, so total mass is conserved.

Question 29Chemistry: particles, reactions and mass

When water boils, bubbles that form in the liquid are:

  1. water vapour (gas) Correct answer.
  2. air
  3. hydrogen and oxygen
  4. carbon dioxide

Explanation

The bubbles in boiling water are water vapour formed when liquid water changes to gas throughout the liquid.

Question 30Chemistry: particles, reactions and mass

Which element is a metal?

  1. Sulfur (S)
  2. Oxygen (O)
  3. Chlorine (Cl)
  4. Sodium (Na) Correct answer.

Explanation

Sodium is a soft reactive metal in Group 1. Sulfur, chlorine and oxygen are non-metals.

Question 31Chemistry: particles, reactions and mass

A sample of pure water is found to have a pH of 7. This means the water is:

  1. neutral Correct answer.
  2. acidic
  3. basic
  4. ionised

Explanation

Pure water has a pH of 7, which is neutral - neither acidic nor basic.

Question 32Chemistry: particles, reactions and mass

Iron rusting is an example of:

  1. neutralisation
  2. rapid combustion
  3. a physical change
  4. slow oxidation Correct answer.

Explanation

Rusting is the slow oxidation of iron in the presence of oxygen and water, forming hydrated iron oxide.

Question 33Chemistry: particles, reactions and mass

In a neutral atom, the number of electrons equals the number of:

  1. ions
  2. neutrons
  3. nucleons
  4. protons Correct answer.

Explanation

A neutral atom has equal positive (proton) and negative (electron) charges, so the numbers of protons and electrons are equal.

Question 34Chemistry: particles, reactions and mass

Which change increases the rate of dissolving of a solid in water most directly?

  1. Cooling the water
  2. Using larger crystals
  3. Stirring the mixture Correct answer.
  4. Adding more water at the same temperature without stirring

Explanation

Stirring moves dissolved particles away from the solid surface and brings fresh solvent into contact, increasing the dissolving rate.

Question 35Chemistry: particles, reactions and mass

Calcium carbonate decomposes on strong heating to calcium oxide and which gas?

  1. Nitrogen
  2. Oxygen
  3. Carbon dioxide Correct answer.
  4. Hydrogen

Explanation

CaCO3 -> CaO + CO2. The gas released is carbon dioxide, which turns limewater milky.

Question 36Chemistry: particles, reactions and mass

Which separation technique is best for obtaining pure water from salt water?

  1. Filtration
  2. Chromatography
  3. Magnetism
  4. Distillation Correct answer.

Explanation

Distillation boils the water and condenses the vapour, leaving the salt behind and collecting pure water.

Question 37Biology: cells, inheritance and evidence

Which process do plants use to make glucose from carbon dioxide and water, using light energy?

  1. Respiration
  2. Digestion
  3. Photosynthesis Correct answer.
  4. Transpiration

Explanation

Photosynthesis uses light energy to convert CO2 and water into glucose and oxygen in the chloroplasts.

Question 38Biology: cells, inheritance and evidence

Which gas is released by plants during photosynthesis?

  1. Hydrogen
  2. Oxygen Correct answer.
  3. Carbon dioxide
  4. Nitrogen

Explanation

The overall reaction 6CO2 + 6H2O -> C6H12O6 + 6O2 shows that oxygen is released as a by-product.

Question 39Biology: cells, inheritance and evidence

In humans, which blood vessels carry blood away from the heart?

  1. Arteries Correct answer.
  2. Capillaries
  3. Valves
  4. Veins

Explanation

Arteries carry blood away from the heart, usually under high pressure; veins carry blood back to the heart.

Question 40Biology: cells, inheritance and evidence

In the human digestive system, where does most absorption of digested nutrients occur?

  1. Large intestine
  2. Mouth
  3. Stomach
  4. Small intestine Correct answer.

Explanation

The small intestine has a large surface area (villi) and is where most digested nutrients are absorbed into the blood.

Question 41Biology: cells, inheritance and evidence

Which structure in a plant cell is not present in an animal cell?

  1. Cell wall Correct answer.
  2. Nucleus
  3. Mitochondria
  4. Cell membrane

Explanation

Plant cells have a rigid cellulose cell wall; animal cells do not. Both have a nucleus, membrane and mitochondria.

Question 42Biology: cells, inheritance and evidence

Which gas is taken in and used by cells during respiration?

  1. Oxygen Correct answer.
  2. Methane
  3. Carbon dioxide
  4. Nitrogen

Explanation

Aerobic respiration uses oxygen to release energy from glucose: glucose + oxygen -> carbon dioxide + water + energy.

Question 43Biology: cells, inheritance and evidence

A tall pea plant (Tt) is crossed with a short pea plant (tt). What fraction of offspring is expected to be short? (T = tall, t = short)

  1. 1/2 Correct answer.
  2. All tall
  3. 3/4
  4. 1/4

Explanation

Cross Tt × tt gives offspring Tt, Tt, tt, tt. Half are tt (short), so the fraction is 1/2.

Question 44Biology: cells, inheritance and evidence

Which group of organisms breaks down dead material and returns nutrients to the soil?

  1. Carnivores
  2. Herbivores
  3. Decomposers (bacteria and fungi) Correct answer.
  4. Producers

Explanation

Decomposers such as bacteria and fungi break down dead organisms and waste, releasing nutrients back into the environment.

Question 45Biology: cells, inheritance and evidence

Which part of a flowering plant transports water and dissolved minerals from the roots?

  1. Stomata
  2. Xylem Correct answer.
  3. Epidermis
  4. Phloem

Explanation

Xylem vessels carry water and minerals upward from the roots to the rest of the plant.

Question 46Biology: cells, inheritance and evidence

When a person's eye focuses on a near object, the ciliary muscles:

  1. contract, making the lens thicker Correct answer.
  2. close the pupil
  3. relax, making the lens thinner
  4. do not change

Explanation

For near vision the ciliary muscles contract, the suspensory ligaments slacken, and the lens becomes thicker (more curved) to bend light more.

Question 47Biology: cells, inheritance and evidence

Which is the correct word equation for aerobic respiration?

  1. carbon dioxide + water -> glucose + oxygen
  2. glucose + oxygen -> carbon dioxide + water + energy Correct answer.
  3. glucose -> alcohol + carbon dioxide
  4. starch + water -> glucose

Explanation

Aerobic respiration breaks down glucose using oxygen to release energy, producing carbon dioxide and water.

Question 48Biology: cells, inheritance and evidence

A woman with blood group O and a man with blood group AB have children. Which blood groups are possible in their children?

  1. A, B, AB and O
  2. AB only
  3. O only
  4. A and B only Correct answer.

Explanation

The mother is OO and the father is AB. Children receive one allele from each, so they can be AO (group A) or BO (group B) only.

Question 49Biology: cells, inheritance and evidence

Which adaptation helps a cactus survive in a desert?

  1. Leaves reduced to spines to reduce water loss Correct answer.
  2. Large broad leaves
  3. Shallow roots only
  4. Stomata open all day

Explanation

Spines reduce the surface area and water loss, and the thick stem stores water - adaptations to a dry habitat.

Question 50Biology: cells, inheritance and evidence

Which statement about viruses is correct?

  1. They carry out respiration on their own
  2. They can only reproduce inside a living host cell Correct answer.
  3. They feed on dead matter
  4. They are living cells

Explanation

Viruses are not cells and cannot reproduce or carry out metabolism on their own; they must use a host cell's machinery.