Practice Test - NEET MCQ

Explanation:for electromagnetic induction magnet and coil both may move but relative motion between must be present

Explanation:A will become positive with respect to B because current  indused is in clockwise direction

e = NBAω = 20 x 3 x 10^-2 x (3.14 x 0.08 x 0.08) x 50 = 0.603C

average power loss due to joule heating

e = NBAω = NBA²πn = 8 x 0.5 x 0.09 x 2 x 3.14 x 60 = 136V

Solution:

• The first law of thermodynamics states: dQ = dU + dW.
• In an isothermal process, the temperature remains constant.
• This means the change in internal energy (dU) is zero because internal energy is a function of temperature.
• Thus, all the heat supplied (dQ) is used to do work (dW).
• According to the second law of thermodynamics, not all heat can be converted to work, but in this ideal case, internal energy does not increase.

Extensive variable →H (enthalpy), E (Internal energy) and Mass. Since these variables depend on the amount of substance or volume or size of the system.

From the first law of thermodynamics,
we know, dU = dQ - dW ; (work done BY the system is considered +ve)
For an adiabatic process, dQ = 0, and hence, dU = -dW
For an ideal gas expansion, we see that work done
BY the system is +ve (recall the sign convention for work done), i.e., dW > 0.
Therefore, dU is less than 0, and thus, the internal energy decreases.

T_Initial  = t K
Work, W = 9R
Ratio of specific heats, γ = C_p / C_v = 4/3
In an adiabatic process, we have
W = R(T_Final – T_initial) / (1-γ)
9R = R (T_Final – t) / (1 – 4/3)
T_Final – t = 9 (-1/3) = -3
T_Final  = (t-3) K

Alcohols have higher boiling points than aldehydes.

This is 1-phenyl propan-1-one.

Reductive Ozonolysis of alkene forms aldehyde or ketone.

The correct answer is option C
CH_3​CH₂​CONH₂​ (A)⟶ CH₃​ − CH₂ ​− NH₂​ (B)⟶ ​CH_3​ − CH₂ ​− OH
In the above sequence A & B respectively are Br₂​/KOH and HNO₂​
The first step is Hoffmann bromamide degradation reaction in which an amide (propanamide) is converted to an amine  (ethylamine) containing one carbon atom less. The reagent A is bromine in presence of KOH. In the second step, aliphatic primary amine (ethyl amine) reacts with nitrous acid (reagent B) to form aliphatic primary alcohol (ethyl alcohol).
 

Fe + HCl is preferred due to the following reasons:
- Scrap iron i.e Fe is cheap and commercially easily available
- FeCl₂ formed will get hydrolysed and release HCl, so, HCl which is required in the reaction will be produced by itself
- Hence only small amount of HCl is required to initiate the reaction.

Because it produces produced nine plants with round, yellow seeds, three plants with round, green seeds, three plants with wrinkled, yellow seeds and one plant with wrinkled, green seeds.therefore the ratio is 9 : 3 : 3 : 1

 When a homozygous dominant tall pea plant (TT) is crossed with a homozygous recessive dwarf pea plant (tt), all the offspring (F1 generation) will be heterozygous (Tt) and exhibit the dominant tall phenotype. This is a classic example of Mendel's law of dominance, where the dominant allele masks the presence of the recessive allele in the heterozygote

• Variation is the difference between individuals within a population.
• These arise between the progeny and parents/ancestors and form a backbone for natural selection to act on.

A single gene may have two or more phenotypic expressions. The multiple phenotypic effect of a single gene is called pleiotropism. Hence the gene associated with this phenomenon is called Pleiotropic gene.

 Test cross is across made to identify hidden recessive alleles in an individual of unknown genotye. This individual is crossed with one that is homozygous for the allele being investigated (i.e., a homozygous recessive). The homozygous recessive individual may be the parent of the individual being investigated.

DNA molecules are replicated in both meiosis and mitosis.  DNA unwinds and unzips along its base pair chemical bonds.  Free nucleotides then connect to the exposed base pairs on both strands resulting in the formation of the missing side of each new DNA.

A single strand of nucleic acid tagged with a radioactive molecule is calledProbe. Probe is used to know the mechanism of transcription of DNA. Radioactive substance can be easily detected.

The structural gene (z) of the lac operon codes for β-galactosidase. It is responsible for the hydrolysis of polysaccharides. The ‘y’ genes code for permease. It increases the permeability of a cell to β-galactosidase. The ‘a’ genes code for transacetylase.

The DNA segment which serves as ON-OFF switch for transcription is called an operator. Operator attach with template strand to initiate transcription process.

Origin of universe is explained by big bang theory. According to this theory, whole universe was concentrated into single sphere. Due to same unknown region, there was explosion in it that forms different galaxies still moving away from each other.

Fossils are dead remains of plants and animals buried inside the earth crust millions of year ago. Fossils are commonly preserved in sedimentary rock as this kinds of rocks are formed layer by layer in course of time.

• Chimpanzee is closely related to man. DNA content and DNA matching are the same in both.
• This similarity is more than 99% with chimpanzee whereas 94% with a gibbon.

Darwin judged the fitness of an individual by number of offspring the individual produce in particular niche. More the viable offspring formed the more fit the organism in that surrounding.