Which of the following oxidation states are the most characteristic for lead and tin respectiviely?
Options
(a) 2,4 (b) 4,4 (c) 2,2 (d) 4,2
Correct Answer:
2,4
Explanation:
When ns² electrons of outermost shell […]
The frequency of a light wave in a material is 2 x 10¹⁴ Hz and wavelength is 5000Å. The refractive index of material will be
Options
(a) 1.5 (b) 3 (c) 1.33 (d) […]
In a radioactive decay process, the negatively charged emitted β- particles are
Options
(a) the electrons produced as a result of the decay of neutrons inside the nucleus (b) the electrons produced as […]
Nickel shows ferromagnetic property at room temperature. If the temperature is increased beyond Curie temperature, then it will show
Options
(a) anti ferromagnetism (b) no magnetic property (c) diamagnetism (d) paramagnetism
Correct Answer: […]
A charged particle (charge q) is moving in a circle of radius R with uniform speed v. The associated magnetic moment µ is given by
Options
(a) qvR² (b) qvR² / 2 (c) […]
A beam of electron passes undeflected through mutually perpendicular electric and magnetic fields. If the electric field is switched off, and the same magnetic field is maintained, the electrons move
Options
(a) in […]
Two satellites of earth, S₁ and S₂ are moving in the same orbit. The mass of S₁ is four times the mass of S₂. Which one of the following statements is true?
Options
Foolish seedling disease of rice led to the discovery of
Options
(a) abscisic acid (b) cytokinin (c) 2,4-D (d) gibberellin
Correct Answer:
gibberellin
Explanation:
The effect of gibberellins had been known in Japan since […]
An engine has an efficiency of 1/6. When the temperature of sink is reduced by 62⁰C, its efficiency is doubled. Temperature of the source is
Options
(a) 37⁰C (b) 62⁰C (c) 99⁰C (d) […]
For a cubic crystal structure which one of the following relations indicating the cell characteristics is correct?
Options
(a) a ≠ b ≠ c and α = β = γ = 90⁰ (b) […]
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