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Correct option is  A) 0°

Here. V = 100 ± 2 volt and I = 10 ± 0.5 ampere

Expressing limits of error as percentage error,

We have,

V = 100 volt ± \(\frac{2}{100}\) × 100% = 10 volt ± 2% and I = 10 ampere ± \(\frac{0.5}{10}\) × 100%

= 10 ampere ± 5%

∴ R = \(\frac{V}{I}\)

∴ %error in R = %error in V + %error in I

= 2% + 5% = 7%

It comes out without any duration.

The virtual images of distant high objects cause the optical illusion called mirage.

Refractive index.

(d) X-rays 

Electromagnetic radiation, being of high frequency such as X-rays can produce photoelectric effect.

(a) uv radiation

Ultraviolet radiation, being of high frequency, can emit photoelectrons from metals.

The maximum constant velocity acquired by a body while falling freely through a viscous medium is called the terminal velocity V_T .

According to this theorem, “the moment of inertia of a body about a rotational axis is equal to the moment of inertia relative to parallel axis passing through the center of mass plus the product of mass and square of the perpendicular distance between the parallel axis.” i.e,
I = I_CM + Mh²
where : I_CM = moment of inertia about an axis passing through center of mass

M = mass of the body

h = distance between the parallel axis.

Relation between Torque, Moment of Inertia and Angular Acceleration

Let us consider a body on which torque x is applied, is rotating about an axis passing through a constant point and the body also has a constant angular acceleration α. All the particles of the body will have same angular acceleration a but the linear accelerations will be different. Suppose, one particle of the body has mass m₁ and the distance of it from the rotational axis is r₁. Then the linear acceleration of this particle is;
α₁ = r₁α
If \(\vec{F}\) is the force acting on the particle then;
F₁ = mass × acceleration
= \(m_{1} \vec{a}\) = m₁r₁α
The torque of this force along the rotational axis passing through O from the fig. is;
τ₁ = Force (F₁) × distance (r₁)
= m₁r₁α × r = m₁r₁²α
Similarly, if m₂, m₃,… be the masses of other particles and r₂, r₃, … the distances from the rotational axis, then the torque acting on them will be; c₂ = m₂r₂a
τ₂ = m₂r₂²α
τ₃ = m₃ r₃²α
Since, the directions of all the torque is along the same rotational axis. Hence the resultant force (torque) on the body will be the vector sum of all the torques.
τ = τ₁ + τ₂ + τ₁ + …
= m₁r₁²α + m₂r₂²α + m₃r₃²α+ ……..
= (m₁r₁² + m₂r₂² + m₃r₃²) α
τ = (Σ mr²) α
But Σ mr² is the moment of inertia I about the rotational axis. Therefore,
τ = Iα ………….. (1)
Torque = Moment of inertia × Angular Acceleration
Keeping α = 1 rad/s² in the above equation,
τ = I
Hence, the moment of inertia of a body about the rotational axis is equal to the applied torque required to generate unit angular acceleration in the body.

Relation between linear velocity (v) and angular velocity (ω) is,
v = rω
where, r is the radius of the circular path.

Yes; for example the center of mass of a ring is at its center. Which is outside.

E_t = \(\frac{1}{2} M v^{2}\left(1+\frac{K^{2}}{R^{2}}\right)\)
and this relation is obtained from the relation
E_t = \(\frac{1}{2}\) Mv² + \(\frac{1}{2}\) Iω²

Given; ω₀ = 0; α = 3.0 rad/s²; t = 2.0 s;
ω = ?; θ = ?
From first equation of motion,
ω = ω₀ + αt = 0 + 3.0 × 2
or ω = 6.0 rad/s
Now applying second equation,
θ = ω₀t + \(\frac{1}{2}\) αt² = 0 + \(\frac{1}{2}\) × 3 × 2 × 2
or θ = 6.0 rad

Given; α = 4 rad/s²; T = 2.0 × 10^-4 Nm; I = 1, The relation between τ, I and α is,
τ = Iα
∴ \(I=\frac{\tau}{\alpha}=\frac{2.0 \times 10^{-4}}{4}\)
\(=\frac{1}{4} \times 10^{-4}=0.5 \times 10^{-4}\)

or I = 5.0 × 10^-5 kgm²

Moment of inertia of wheel M,
I₁ = 6kg m²
Frequency of rotation,
n₁ = 600 cycles/min.
= \(\frac{600}{60}\) c.s^-1 = 10 c.s^-1
∴ Initial angular velocity,
ω₁ = 2πn₁ = 2π × 10 = 20n rad/s
Angular velocity of joint wheels,
ω₂ = 2πn₂
where, n₂ = 400 c/min = \(\frac{400}{60}\) c/s = \(\frac{20}{3}\) c/ s
∴ ω₂ = 2π × \(\frac{20}{3}\) = \(\frac{40}{3}\)π rad/s 

If the joint moment of inertia be I₂, then by the law of conservation of angular momentum,
I₂ω₂ = I₁ω₁
or I₂ × \(\frac{40}{3} \pi\) = 6020π
or I₂ = 9 kg m²
but I₂ = I_M + I_N
∴ 9 = 6 + I_N
or I_N = 9 – 6 = 3kg m².

Kinetic energy, k = p²/2m where p is the momentum.

Both the masses have same momentum p. The kinetic energy, K is inversely proportional to mass of the body.

Hence light mass body has more kinetic energy because smaller the mass, larger is the kinetic energy.

Yes, for example, when a bomb explodes, linear momentum conserved, but K.E. changes.

In uniform circular motion. 

Oxygen is more electronegative than chlorine, therefore dispersal of negative charge present on chlorine increases from ClO^– to ClO₄ ^– ion because number of oxygen atoms attached to chlorine is increasing. Therefore, stability of ions will increase in the order given below :

ClO^– < ClO₂^– < ClO₃^– < ClO₄^–  

Thus due to increase in stability of conjugate base, acidic strength of corresponding acid increases in the following order

HClO < HClO₂ < HClO₃ < HClO₄

Pure or fuming nitric acid renders metals like iron (Fe) and Al- passive i. e., inactive. This is due to the formation of a thin oxide coating on the surface of the metal which prevents further action.

John Dalton published “A New System of chemical philosophy” in the year of 1808. He proposed the following features, which later became famous as Dalton’s atomic theory.

• Matter consists of tiny, indivisible particles called atoms.
• All the atoms of a given elements have identical properties including mass. Atoms of different elements differ in mass.
• Compounds are formed when atoms of different elements combine in a fixed ratio.
• Chemical reactions involve only the reorganization of atoms. Atoms are neither created nor destroyed in a chemical reaction.

Dalton’s atomic theory could explain all the laws of chemical combination.

• The law of multiple proportion states that, “When two elements A and B form more than one compounds, the masses of element B that combine with a given mass of A are always in the ratio of small whole numbers.
• According to Dalton’s atomic theory, compounds are formed when atoms of different elements combine in fixed ratio.

Hence, 

Dalton’s atomic theory explains the law of multiple proportion.

• The law of conservation of mass states that, “Mass can neither be created nor destroyed” during chemical combination of matter.
• According to Dalton’s atomic theory, chemical reactions involve only the reorganization of atoms. Therefore, the total number of atoms in the reactants and products should be same and mass is conserved during a reaction.

Hence, 

Dalton’s atomic theory explains the law of conservation of mass.

It states that matter can neither be, created nor be destroyed.

Law of definite proportions : 

i. The law states that “A given compound always contains exactly the same proportion of elements by weight”. 

ii. French chemist, Joseph Proust worked with two samples of cupric carbonate; one of which was naturally occurring cupric carbonate and other was synthetic sample. 

He found the composition of elements present in both the samples was same as shown below :

iii. Thus, irrespective of the source, a given compound always contains same elements in the same proportion.

The law states that “a chemical compound, however prepared, contains the same elements combined together in the same fixed proportion by mass”.

The following methods are employed by organisms to cope with stressful conditions:

i. Migrate temporarily from the stressful habitat to a hospitable area, 

ii. suspend activities, 3 

iii. form thick walled spores, 

iv. form dormant seeds, 

v. hibernate during winter, 

vi. aestivate during summer, 

vii. planktons undergo diapause.

(a) In earthworm, a pair of male genital pore is present.

Correct answer is (a) Cyclic AMP

The male and female sex organs mature at different times Sperms develops earlier than the production of ova (protandrous). Hence, self fertilization does not take place in earthworm.

The female reproductive system consists of a pair of ovaries lying in the 3’ segment. Each ovary has finger like projections which contain ova in linear series. Ovarian funnels are present beneath the ovaries which continue into the oviducts.

They join together and open on the ventral side as a single median female genital pore in the 14th segment. Spermathecae or seminal receptacles are three pairs lying in segments 7th , 8th and 9th opening to the exterior on the ventral side between 6th & 7th 7th & 8th and 8th & 9th segments. They receive spermatozoa from the partner and store during copulation.

The region in the eye where the rods and cones are located in Retina.

(a) Photoreceptors.

(b) Thermoreceptors.

(c) Phonoreceptors.

(d) Olfactory receptors.

(e) Gustatory receptors

The collaterial glands present behind the ovaries of female reproductive system cockroach produce ootheca.

Ovaries:

• They are female gonads but also act as an endocrine gland. 
• They secrete three types of hormones. 
• Its follicular cells & corpus luteum perform an endocrine function. 
• In woman, the ovaries activate as an age of 12 years. It is called as beginning of puberty.
• The follicular cells under the control of FSH secrete estrogen hormone which is also called as estradiol or feminizing hormone. 
• It is a steroid hormone and performs the following functions: 
• It controls oogenesis 
• It provides secondary sexual characters 
• It controls menstrual and oestrous cycles. 
• It stimulates the development of mammary glands. 
• It controls female sexual accessory organs. 
• It controls sexual behaviour 
• The corpus luteum of the ovaries secrete progesterone under the control of LH. 
• The progesterone is a steroid hormone which is also called a pregnancy hormone. It performs the following functions: 
• It prepares the uterus for embryonic development. The uterine wall becomes more muscular, glandular & vascular. 
• It helps in implantation of the embryo. 
• It inhibits oxytocin & ovulation during pregnancy. 
• In woman, the corpus luteum also secretes relaxin hormone at the time of completion of embryonic development. 
• This hormone helps in parturition by relaxing pubic symphysis.

(a) Oval window is located in the middle ear. It helps in setting the fluid in the cochlear canals into vibration.

(b) Cochlea is located in the inner ear. It helps in transmitting impulses to the brain via the auditory nerve.

(c) Semicircular canals are located in the inner ear. These help in maintaining the dynamic equilibrium of the body.

(d) Utriculus is located in the inner ear. It joins the semi-circular canals to cochlea. It also helps in maintaining static balance of the body.

(a) Testosterone.

(b) Progesterone and oestrogen.

Following are the consequences of using fossil fuels. 

• Global warming will result due to increase in the level of Carbon dioxide, 
• Sulphur oxides causes acid rain.
• Burning of fossil fuels will result in accumulation of smog in big cities which will result in decreased visibility.
• Air pollution leads to health hazrds to humans and animals. 

Steps to minimise the pollution caused by various sources of energy including non conventional sources of energy. 

• Use of public transport.
• Use of vehicles like electric bikes and bi-cycle that can reduce air pollution.
• Adopting 3R’s policy- reduce, reuse and recycyle. 
• Afforestation

They have hard calcium carbonate structure which they use as skeleton. They have a spiny body

Coelom is filled with blood in case of animal groups having an open circulatory system. The open circulatory system is a type of circulatory system in which blood is pumped by the heart directly into the body cavities, where tissues are surrounded by the blood and not into blood vessels.

Pseudocoelom is the type of coelom present in the members of phylum Nemathelminthes/ Aschelminthes. In these organisms the coelom is present in the form of packets or pouches

Semolina (Shevaya) are made by drying them in the sun. Since they are dried in sun, the water content in them is completely lost, hence they can be stored for longer time. On the other hand, kheer is made by using milk and milk is a highly perishable’’ product, hence kheer gets spoilt quickly.

When the foodstuffs are preserved in airtight containers, the microorganisms are first destroyed and it is ensured that water or air does not enter the food stuff.

The foodstuff smells foul and have unpleasant appearance. There is even growth of fungus on foodstuffs.

Changes that occur in spoilt food: (a) Taste changes (b) Colour of the food change (c) Presence of black, white patch (fungus) on food (d) Unpleasant smell (e) Nutritive value reduces.