Doubtly
@Doubtly · Joined Feb 2021
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- Lippe’s loop is a type of contraceptive used as: 1) Cervical barrier 2) Vault barrier 3) Non-Medicated IUD 2
- Which of the following functions is not performed by secretions from salivary glands? 4) Digestion of disaccharides 2
- Which of the following is a correct statement? 1) Cyanobacteria area a group 1) Cyanobacteria area a group of autotrophic organisms classified under Kingdom Monera 1
- Select the incorrect statement with respect to acquired immunity. 4) Acquired immunity is non-specific type of defense present at the time of birth. 1
- If a colour blind female marries a man whose mother was also a colour blind, what are the chances of her option 4 is correct that is 4) 100% 2
- Which of the following is not a desirable feature of a cloning vector? 4) Presence of two or more recognition sites 2
- Which one of the following statements is correct? 1) The atrio-ventricular node (AVN) generates an acti 3) Blood moves freely from atrium to the ventricle during joint diastole. 1
- Select the incorrect statement regarding synapses: 4) Impulse transmission across a chemical synapse is always faster than that across an electrical synapse 1
- Which of the following statements is not true? 4) Flippers of penguins and dolphins are a pair of homologous organs 1
- The frequency of light emitted for the transition n = 4 to n = 2 of He+ is equal to the transition in H atom (2) n = 2 to n = 1 2
- Ionisation energy of He+ is 19.6×10-18J atom-1. The energy of the first stationary state (n = 1) of Li2+ is (3) -4.41×10⁻¹⁷ J atom^(-1 ) Given I.E = 19.6×10⁻¹⁸ I.E ∝ z² (I.E) Li²⁺/He⁺ = (9/4)×19.6×10⁻¹⁸ = -4.41×10⁻¹⁷ 1
- The energy required to break one mole of Cl–Cl bonds in Cl2 is 242 kJ mol-1. The longest wavelength of light capable (1) 494 nm We have B.E = 242KJ/Mol E = h_cN_A/λ ∴ λ = h_cN_A/E = 3×10⁸×6.626×10⁻³⁴×6.02×10²³/(242×10³) = 0.494×10⁻³×10³ = 494 nm 1
- The radius of the second Bohr orbit for the hydrogen atom is : (4) 2.12 A Radius of n^th Bohr orbit in H atom = 0.53 n²/Z For hydrogen Z = 1 Radius of 2^(nd )Bohr orbit in H atom = 0.53 ×2²/1 = 2.12 1
- Calculate the wavelength (in nanometer) associated with a proton moving at 1.0×103ms-1 (4) 0.40 nm Given m_p = 1.67×10⁻²⁷kg h = 6.63×10⁻³⁴Js v = 1.0×10³ms⁻¹ We know wavelength λ = h/mv ∴λ = 6.63×10⁻³⁴/(1.67×10^(-27 )× 1.0×10³)... 1
- if the kinetic energy of an electron is increased four times, the wavelength of the de-Broglie wave associated (2) Half Answer: The wavelength λ is inversely proportional to the square root of kinetic energy. So if KE is increased 4 times, the wavelen... 1
- If an electric dipole is kept in a uniform electric field then resultant electric force on it is : (a) always zero 2
- The unit of electric dipole moment is (a) newton (b) coulomb (c) farad (d) debye (d) debye 2
- The SI unit of electric flux is (a) N C-1 m-2 (b) N C m-2 (c) N C-2 m2 (d) N C-1 m2 (d) N C-1 m2 2