Which of the following statements are true regarding alternating current:
(A) In an a.c. circuit containing resistance only, a.c. power is expressed in the same form as d.c. power (\( P = I^2 R \)), using a special value of current called root mean square (rms) or effective current, denoted by \( I_{rms} \).
(B) A phasor is a vector.
(C) Resonance phenomenon is exhibited by a circuit even if both L and C are not present in the circuit.
(D) For circuits used for transporting electric power, a low power factor implies less power loss in transmission.
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Two cells of emf 10 V and 6 V, each having internal resistances of \(2 \Omega\) are connected in parallel across points A and B. The equivalent emf of the cells is

Match List - I with List - II.

List - I (Electromagnetic waves)	List - II (Uses)
(A) Radio waves	(I) Aircraft navigation
(B) Ultraviolet rays	(II) Physical therapy
(C) Infrared waves	(III) Television communication systems
(D) Microwaves	(IV) Kill germs in water purifiers

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Many features of the nuclear binding force are summarised below : Choose the correct statement.
(A) Coulomb force acting between two protons inside the nucleus is much weaker than Nuclear force between them
(B) Between proton-proton inside nucleus gravitational force is stronger than nuclear force
(C) Nuclear force between two nucleons falls rapidly to zero as their distance is more than a few femtometer
(D) Nuclear forces between proton-proton, neutron - proton and neutron-neutron is approximately same when distance between them is same.
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A wire of resistance 20 Ω is bent to form a complete circle. What will be its resistance between two diametrically opposite points?

The following have zero average value in a plane electromagnetic wave

An \( \alpha \) particle and a proton enters a region of uniform magnetic field B with same momentum at right angle to magnetic field. The ratio of the radii of the circular paths of \( \alpha \) particle to proton is:

Which amino acids are present in the histone octamer that contribute to the stable packaging of DNA?

Heavy water and __________ is one of the substance used as moderator in reactors.

For the function \(f(x)=x^{1 / x}, x>0\), which of the following are correct?
(A) \(x=0\) is the only point where extremum may occur.
(B) The given function is maximum at \(x=e\).
(C) The function has no extreme value for \(x>0\).
(D) The maximum value of the function \(f(x)\) is \(e^{1 / e}\)
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Select the statements which hold true for immune system:
A. Innate immunity or nonspecific immunity is present at the time of birth.
B. Acquired immunity is never pathogen specific
C. Cytokine barriers are a part of innate immunity
D. Rheumatoid arthritis is an auto-immune disease
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The correct statements for the activation energy of a reaction are:
(A) Activation energy is the energy difference between the activated complex and the total energy of the reactants.
(B) Higher is the activation energy, the faster is the rate of reaction.
(C) Catalyst increases the rate of the reaction by following the path of lower activation energy.
(D) In the Arrhenius equation, \(E_a\) corresponds to the activation energy
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Answer the question on basis of passage given below :
Alcohols and phenol are formed when a hydrogen atom in a hydrocarbon, aliphatic and aromatic respectively, is replaced by \(\text{-OH}\) group. The substitution of a hydrogen atom in a hydrocarbon by an alkoxy or aryloxy group forms ethers. Alcohols and phenol consist of two part, an alkyl/aryl group and a hydroxyl group. The properties of alcohols and phenols are primarily due to the hydroxyl group. The nature of alkyl and aryl groups simply modify these properties. Alcohol react both as nucleophiles and electrophiles whereas in phenols, the reactions that take place on the aromatic ring are electrophilic subtitution reactions.
Aspirin is an acetylation product of :