NEET UG Free Practice Test Day 36

NEET UG Free Practice Test Day 36: Preparing consistently is the key to success in the highly competitive NEET UG. To help aspirants strengthen their preparation, we bring you NEET UG Free Practice Test Day 36, designed to test your understanding of important concepts from Physics, Chemistry, and Biology.

These daily practice questions are curated according to the latest exam pattern and difficulty level so that students can evaluate their performance and improve their problem-solving speed. Make sure you attempt the test sincerely and analyze your mistakes to make your preparation more effective.

PHYSICS

Q.1. A block of mass $m$ is attached to two identical springs of spring constant $k$ on a rough horizontal surface with coefficient of kinetic friction ${\mu }_k$. The springs are fixed at the walls on both sides, and the natural length of each spring is $L$. The block is displaced by $x_0$ to one side and released from rest. Assuming $x_0$ is large enough that the block crosses the equilibrium point once before stopping, what is the speed of the block at the equilibrium position?

A. $v=\sqrt{{\displaystyle \frac{k}{m}}(x_0^2-x_f^2)-4{\mu }_{k}g{x}_0}$

B. $v=\sqrt{{\displaystyle \frac{2k}{m}}(x_0^2-x_f^2)-4{\mu }_{k}g{x}_0}$

C. $v=\sqrt{{\displaystyle \frac{2k}{m}}{x}_0^2-4{\mu }_{k}g{x}_0}$

D. $v=\sqrt{{\displaystyle \frac{k}{m}}{x}_0^2-2{\mu }_{k}g{x}_0}$

Q.2. A non-uniform rod of length $L$ has linear mass density $\lambda (x)={\lambda }_0{\displaystyle \frac{x}{L}}$, where $x$ is measured from the left end. The rod is pivoted about the left end and held horizontally, then released from rest in a uniform gravitational field g. What is its initial angular acceleration about the pivot?

A. $\alpha ={\displaystyle \frac{3g}{L}}$

B. $\alpha ={\displaystyle \frac{2g}{L}}$

C. $\alpha ={\displaystyle \frac{g}{L}}$

D. $\alpha ={\displaystyle \frac{3g}{2L}}$

Q.3. A small bead of mass $m$m can slide without friction on a circular ring of radius $R$ that lies in a vertical plane. The ring rotates with constant angular speed $\omega$ about a vertical diameter. In the rotating frame of the ring, what is the condition on $\omega$ω for the equilibrium at the lowest point to be stable?

A. ${\omega }^2>{\displaystyle \frac{2g}{R}}$

B. ${\omega }^2>{\displaystyle \frac{g}{R}}$

C. ${\omega }^2<{\displaystyle \frac{g}{R}}$

D. ${\omega }^2<{\displaystyle \frac{2g}{R}}$

Q.4. A thin wire bent into a semicircle of radius $R$ lies in the $xy$-plane with its diameter along the $x$-axis. It carries a current I. A uniform magnetic field $\vec{B}=B_0\widehat{z}$ is present. What is the magnitude of the net magnetic force on the semicircular part of the wire?

A.$F=I{B}_{0}R$

B. $F=2I{B}_{0}R$

C. $F=2I{B}_0{R}^2$

D. F=0

Q.5. A particle of mass $m$ moves in one dimension under the potential $V(x)={\displaystyle \frac{1}{4}}a{x}^4-{\displaystyle \frac{1}{2}}b{x}^2$ with $a,b>0$. It is released from rest at $x=x_0>0$ with total energy $E$. For bound motion between $-x_0$ and $+x_0$, what is the time period of small oscillations about $x=0$?

A. $T=2\pi \sqrt{{\displaystyle \frac{m}{b}}}$

B. $T=2\pi \sqrt{{\displaystyle \frac{m}{2b}}}$

C. $T=2\pi \sqrt{{\displaystyle \frac{m}{2(b-a{x}_0^2)}}}$

D. $T=2\pi \sqrt{{\displaystyle \frac{m}{b-a{x}_0^2}}}$

CHEMISTRY

Q.6. One mole of an ideal monoatomic gas is taken from state A to state B along two different reversible paths in a $P\text{–}V$ diagram. In path 1, the gas is first heated at constant volume from $T_1$ to $2T_1$, then expanded isothermally to volume $2V_1$. In path 2, the gas is first expanded isothermally at $T_1$ from $V_1$ to $2V_1$, then heated at constant pressure to reach the same final state B. If the enthalpy change of the gas in path 1 is $\mathrm{\Delta }{H}_1$ and in path 2 is $\mathrm{\Delta }{H}_2$, and if the heat capacities are temperature independent, the correct relation is:

A. $\mathrm{\Delta }{H}_1<\mathrm{\Delta }{H}_2$

B. $\mathrm{\Delta }{H}_1=\mathrm{\Delta }{H}_2$

C. Sign of $\mathrm{\Delta }{H}_1-\mathrm{\Delta }{H}_2$ depends on $T_1$

D. $\mathrm{\Delta }{H}_1>\mathrm{\Delta }{H}_2$

Q.7. In the Cannizzaro reaction, which condition is essential for disproportionation of an aldehyde to occur?

A. Strong base and a non-enolizable aldehyde

B. Acidic medium with concentrated $H_{2}S{O}_4$

C. Use of molecular oxygen as oxidant

D. Presence of at least one α-hydrogen on the aldehyde

Q.8. In the Aldol condensation of acetaldehyde under base, which intermediate directly leads to the formation of the C−C bond in the β-hydroxy aldehyde product?

A. The enol formed under acidic conditions

B. The geminal diol formed by hydration of acetaldehyde

C. The enolate ion formed by deprotonation at the $\alpha$α-carbon

D. The alkoxide formed after nucleophilic addition to the carbonyl

Q.9. In the Sandmeyer reaction, what role does cuprous halide (e.g., $CuCl$) play in converting a diazonium salt to an aryl halide?

A. It acts purely as a reducing agent to destroy the diazonium ion

B. It is only a spectator ion providing chloride ions

C. It serves as a catalyst forming a transient aryl radical intermediate

D. It protonates the diazonium group to increase its leaving ability

Q.10. In the Finkelstein reaction converting $RCl$ to $RI$ using $NaI$ in dry acetone, which factor most strongly drives the reaction to completion?

A. Higher nucleophilicity of $I^{-}$ compared to $C{l}^{-}$ in acetone

B. Low bond dissociation energy of the $C-I$ bond

C. Oxidation of $I^{-}$ to $I_2$during the reaction

D. Formation of insoluble $NaCl$ that precipitates from acetone

BIOLOGY

Q.11. A child presents with severe combined immunodeficiency, recurrent fungal infections, and markedly reduced numbers of functional T lymphocytes. Genetic studies reveal a mutation impairing the maturation of thymic epithelial cells derived from pharyngeal pouch endoderm. Which additional developmental abnormality is most likely in this child?

A. Hypoplasia of the parathyroid glands leading to hypocalcemic tetany

B. Absence of C cells in the thyroid leading to reduced calcitonin

C. Agenesis of the anterior pituitary leading to panhypopituitarism

D. Defective formation of Meckel’s diverticulum from the vitelline duct

Q.12. A researcher uses CRISPR-Cas9 to knock out the gene encoding a key transcription factor required for the differentiation of hematopoietic stem cells into both B lymphocytes and osteoclasts. Which clinical picture best reflects the combined outcome of this mutation in a human patient?

A. Recurrent bacterial infections, reduced immunoglobulin levels, and increased bone density with brittle bones

B. Severe eosinophilia, heightened allergic responses, and osteoporosis with frequent fractures

C. Hemolytic anemia, increased reticulocyte count, and osteomalacia with low vitamin D levels

D. Polycythemia, increased blood viscosity, and reduced bone density due to marrow expansion

Q.13. During an outbreak, a population of bacteria exposed to a new antibiotic shows a rapid decline followed by regrowth. Genomic analysis reveals that surviving bacteria have acquired a plasmid carrying a gene for an enzyme that modifies the antibiotic. The plasmid is also found in different species in the same environment. Which combination of genetic mechanisms best explains the origin and spread of this resistance?

A. Vertical transmission of a chromosomal mutation through binary fission without plasmid involvement

B. Gene amplification of an existing chromosomal resistance gene in all species independently

C. Transduction by bacteriophages alone introducing the resistance gene into all species simultaneously

D. Mutation in a single bacterium followed by horizontal transfer via conjugation and transformation between species

Q.14. A biochemist studies an enzyme in the glycolytic pathway that shows sigmoidal kinetics and is allosterically inhibited by ATP and activated by AMP and fructose-2,6-bisphosphate. In hepatocytes after a carbohydrate-rich meal, insulin is high. Which enzyme is being studied, and what is its primary regulatory role in metabolism?

A. Phosphofructokinase-1; committing glucose to glycolysis by controlling the rate-limiting step

B. Hexokinase; trapping glucose in cells by phosphorylating it to glucose-6-phosphate

C. Pyruvate kinase; converting phosphoenolpyruvate to pyruvate and generating ATP

D. Glucose-6-phosphatase; releasing free glucose into the bloodstream from the liver

Q.15. A man with blood group A (genotype $I^{A}i$) marries a woman with blood group B (genotype $I^{B}i$). They have four children. Which of the following blood group combinations in their children would most strongly suggest that a hospital mix-up occurred?

A. A, A, B, O

B. A, B, AB, O

C. AB, AB, B, A

D. O, O, A, B

Regular practice plays a crucial role in improving accuracy and confidence for NEET UG. After completing today’s Day 36 Practice Test, review the explanations carefully and identify the topics that need more revision.

To support your preparation, Edufever is also providing free study materials designed to help aspirants aim for 650+ scores in NEET UG. You can download these resources easily from the link provided below in the article. Stay consistent with your preparation and keep visiting daily for more practice tests that will help you stay exam-ready.

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ANSWERS & EXPLANATIONS

Ans. 1. C. is: $v=\sqrt{{\displaystyle \frac{2k}{m}}{x}_0^2-4{\mu }_{k}g{x}_0}$. You start by evaluating the initial elastic potential energy stored in both springs and equate the decrease in this energy to the sum of kinetic energy gained plus work done against friction.

Ans.2. A. $\alpha ={\displaystyle \frac{3g}{L}}$ The non-uniform mass density $\lambda (x)\propto x$ makes the right side of the rod heavier, shifting the center of mass to $x_{cm}={\displaystyle \frac{2L}{3}}$. That increases the torque $\tau =Mg{x}_{cm}$ compared to a uniform rod. 

Ans. a 3. C. is: ${\omega }^2<{\displaystyle \frac{g}{R}}$. Getting the right condition requires correctly deriving the effective potential in the rotating frame and performing a proper Taylor expansion up to second order in $\varphi$. The sign of the quadratic term determines whether the equilibrium is a minimum (stable) or maximum (unstable). Any discrepancy in the coefficient leads to an incorrect boundary like $2g\mathrm{/}R$.

Ans.4. A. F=2IB0R. Dimensional analysis alone can guide you: the basic force element is $I{B}_{0}L$, with $L$ a length. A term like $R^2$ would incorrectly give units of $N\cdot m$. Physically, as you double the radius, the length of the semicircle doubles and so should the net force, leading to a linear dependence on $R$, not quadratic.

Ans. 5. A. $\omega ={\displaystyle \frac{qB}{\gamma m_0}}$. In special relativity, the inertial mass in motion is effectively $\gamma m_0$ for transverse acceleration, so it is this factor that must appear in the denominator of the cyclotron frequency.

Ans.6. B. ΔH1=ΔH2. For state functions, the total change between the same two states is unique. Changing the sequence of isochoric, isobaric, or isothermal steps does not affect $\mathrm{\Delta }H$; only the path-dependent quantities like $q$ and $w$ change.

Ans.7. A. Strong base and a non-enolizable aldehyde. In the Cannizzaro reaction, hydroxide attacks the carbonyl carbon of an aldehyde lacking $\alpha$α-hydrogen, forming an alkoxide that serves as a hydride donor to another aldehyde molecule. This intramolecular redox process yields a carboxylate and an alcohol. The requirement for non-enolizable aldehydes avoids competing aldol chemistry and ensures that the base-promoted hydride transfer pathway dominates.

Ans.8. C. The enolate ion formed by deprotonation at the $\alpha$α-carbon. In basic medium, deprotonation at the α-position gives a resonance-stabilized enolate, which is a powerful carbon nucleophile. This enolate attacks the carbonyl carbon of another aldehyde molecule, directly forming the new C−C bond that defines the Aldol product. The alkoxide that results from this step only appears after the bond-forming event has already occurred.

Ans.9. C. It serves as a catalyst forming a transient aryl radical intermediate. The commonly accepted mechanism involves $C{u}^{+}$ reducing the diazonium ion to an aryl radical with loss of $N_2$, and then the radical couples with the halide coordinated to copper. This process both introduces the halide into the aromatic ring and regenerates the copper catalyst, explaining why $CuX$ is required specifically rather than just any chloride source.

Ans.10. D. Formation of insoluble $NaCl$ that precipitates from acetone. In acetone, $NaI$ is soluble, while $NaCl$ is not. As $NaCl$ forms and precipitates, the equilibrium is shifted toward further formation of $RI$, effectively making the halogen exchange irreversible. This phase-separation effect is the major thermodynamic driving force behind the success of the Finkelstein substitution.

Ans.11. A. Hypoplasia of the parathyroid glands leading to hypocalcemic tetany. The anterior pituitary (adenohypophysis) forms from Rathke’s pouch, an ectodermal outgrowth from the roof of the primitive mouth, not from pharyngeal pouches. In contrast, the thymus and inferior parathyroids both originate from the third pharyngeal pouch endoderm. Thus, a lesion affecting thymic epithelial cells would also affect these parathyroids. 

Ans.12. A. Recurrent bacterial infections, reduced immunoglobulin levels, and increased bone density with brittle bones. Eosinophils are granulocytes involved in responses to parasites and allergic reactions, regulated by different transcription factors than those governing B lymphocytes and osteoclasts. Osteoporosis involves increased bone resorption or decreased formation, resulting in reduced bone density, which is the opposite of what you expect with impaired osteoclast function.

Ans.13. D. Mutation in a single bacterium followed by horizontal transfer via conjugation and transformation between species. Transduction involves bacteriophages transferring DNA from one bacterium to another, often moving chromosomal fragments or occasionally plasmid DNA. However, the question specifically notes a shared plasmid carrying the resistance gene across different species, which is more characteristic of conjugative plasmids spreading via cell-to-cell contact and transformation.

Ans.14. A. Phosphofructokinase-1; committing glucose to glycolysis by controlling the rate-limiting step. Hexokinase catalyzes the phosphorylation of glucose to glucose-6-phosphate and does have regulatory features, but in the liver, the isoenzyme glucokinase is more important and is regulated differently, mainly by glucose concentration and sequestration in the nucleus. 

Ans. 15. B. From parents $I^{A}i$ and $I^{B}i$, the possible genotypes of children are $I^A{I}^B$ (AB), $I^{A}i$IAi (A), $I^{B}i$ (B), and ii (O). Therefore, all four major phenotypes A, B, AB, and O can appear. This combination is fully compatible with the stated parental genotypes and does not suggest a mix-up.