The radius of hydrogen atom is about
a) 5 x 10-11 m b) 5 x 10-11 cm c) 5 x 10-11 mm d) 5 x 10-11 dm

1 Answer

Answer :

a) 5 x 10-11 m

Related questions

Description : The value of first quantized Bohr orbit radius of hydrogen atom is a) 0.0053 nm b) 5.3 nm c) 0.053 nm d) 0.053 cm

Last Answer : c) 0.053 nm

Description : The quantized Bohr orbit radius of electron in hydrogen atom is given by a) n2 r3 b) nr1 c) n2 r2 d) n2 r1

Last Answer : d) n2 r1

Description : For Hydrogen atom, the allowed stationary orbits are those whose orbital angular momentum is equal to an integral multiple of h i.e., mvr = a) nh/2π b) nh x 2π c) nh / 2λ d) nh / 2πλ

Last Answer : a) nh/2π

Description : Which of the following wavelengths where absorption of electromagnetic waves becomes peak due to vibrational resonances in the water vapor molecule? A. 1.35 cm and 1.7 mm B. 1.5 mm and 5 mm C. 1.35 dm and 1.7 cm D. 1.5 cm and 5mm

Last Answer : A. 1.35 cm and 1.7 mm

Description : Which of the following wavelengths where absorption of electromagnetic waves becomes peak due to vibrational resonances in the water vapor molecule? A. 1.35 cm and 1.7 mm B. 1.5 mm and 5mm C. 1.35 dm and 1.7cm D. 1.5 cm and 5 mm

Last Answer : A. 1.35 cm and 1.7 mm

Description : According to Bohr’s theory, the fourth stationary orbit of electrons in the hydrogen atom is a) 4 (0.053 nm) b) 9 (0.053 nm) c) 16 (0.053 nm) d) 25(0.053 nm)

Last Answer : c) 16 (0.053 nm)

Description : An α particle moves perpendicular to a constant magnetic field of strength 1.2 T in a circular path of radius 0.7 m. The speed of α particle in ms-1 is ______________ a) 2.7 × 107 b) 2.6 × 107 c) 3.2 × 107 d) 2.0 × 107

Last Answer : a) 2.7 × 107

Description : A rheostat has 100 turns of a wire of radius 0.4 mm having resistivity `4.2xx10^(-7) Omega`m. The diameter of each turn is 3 cm. What is the maximum v

Last Answer : A rheostat has 100 turns of a wire of radius 0.4 mm having resistivity `4.2xx10^(-7) ... the maximum value of resistance that it can introduce ?

Description : In hydrogen atom, the electron is making `6.6xx10^(15) rev//sec` around the nucleus in an orbit of radius `0.528 A`. The magnetic moment `(A-m^(2)) wi

Last Answer : In hydrogen atom, the electron is making `6.6xx10^(15) rev//sec` around the nucleus in an orbit of radius `0. ... ` C. `1xx10^(-23)` D. `1xx10^(-27)`

Description : If electron has to be confined in the nucleus, its speed would have to be greater than a) 1010 cm/s b) 1010 m/s c) 1020 m/s d) 1020 cm/s

Last Answer : b) 1010 m/s

Description : The S.I. unit of Rydberg’s constant is a) m-2 b) m-1 c) cm-1 d) cm-2

Last Answer : b) m-1

Description : Calculate the radius of the first and second orbit of sodium atom `(Z=11)`. `(h=6.6xx10^(-34) J s, e=1.6xx10^(-19) C` and `m=9.1xx10^(-31) kg.)`

Last Answer : Calculate the radius of the first and second orbit of sodium atom `(Z=11)`. `(h=6.6xx10^(-34) J s, e=1.6xx10^(-19) C` and `m=9.1xx10^(-31) kg.)`

Description : The electron with change `(q=1.6xx10^(-19)C)` moves in an orbit of radius `5xx10^(-11)`m with a speed of `2.2xx10^(6)ms^(-1)`, around an atom. The equ

Last Answer : The electron with change `(q=1.6xx10^(-19)C)` moves in an orbit of radius `5xx10^(-11)`m with a speed of `2. ... -3)A` C. `1.12xx10^(-9)A` D. `1.12A`

Description : In the phenomenon of Laser production, atom can reside in the meta stable state for a) ~ 10-3 s b) ~ 10-8 s c) ~ 10-4 s d) ~ 10-10 s

Last Answer : a) ~ 10-3 s

Description : In the phenomenon of Laser production, atom can reside in the excited state only for a) 10-6 s b) 10-7 s c) 10-8 s d) 10-9 s

Last Answer : c) 10-8 s

Description : Calculate the energy of hydrogen atom in the ground state given that the after Bohr orbit og hydrogen is `5xx10^(-11)m` and electronic charge is `1.6x

Last Answer : Calculate the energy of hydrogen atom in the ground state given that the after Bohr orbit og hydrogen is ` ... electronic charge is `1.6xx10^(-19) C`.

Description : The gap between the two halves of axle pulley should be  a. 0.5 – 1.0 mm c. 3.0 – 4.0 mm b. 2.0 – 3.0 mm d. 5.0 – 5.5 mm

Last Answer : c. 3.0 – 4.0 mm

Description : In human flesh, the three light elements which predominate, and allow greater amount of incident X-rays to pass through them are a) oxygen, nitrogen , hydrogen b) oxygen, hydrogen, helium c) oxygen, hydrogen, carbon d) carbon, nitrogen, oxygen

Last Answer : c) oxygen, hydrogen, carbon

Description : The transfer function of a system is 10/(1+s) when operating as a unity feedback system, the steady state error to a step input will be a) 0 b) 1/11 c) 10 d) Infinity

Last Answer : Ans: 1/11

Description : The value of Rydberg’s constant is a) 1.0974 x 10-7 m-1 b) 1.0974 x 107 m-1 c) 1.0974 x 107 m-2 d) 1.0974 x 10-7 m-2

Last Answer : b) 1.0974 x 107 m-1

Description : The force between two long parallel conductors is inversely proportional to (a) radius of conductors (b) current in one conductor (c) product of current in two conductors (d) distance between the conductors

Last Answer : (d) distance between the conductors

Description : A proton moves in a uniform magnetic field in a circular path of radius R. If the energy of proton is doubled then the new radius becomes a) R √2 b) 2R c) R 2 d) √2 R

Last Answer : d) √2 R

Description : Specific resistance of a wire a. will depend on its length b. will depend on its radius c. will depend on the type of material of the wire d. will depend on none of the above

Last Answer : c. will depend on the type of material of the wire

Description : Electron can exist in the atom but outside the nucleus because a) speed of electron is equal to the speed of light b) speed of electron is more than speed of light c) speed of electron is less than speed of light d) None of these

Last Answer : c) speed of electron is less than speed of light

Description : The emission in which the atom emits a photon of energy hf = E2 – E1 , in any arbitrary direction is a) Spontaneous emission b) stimulated emission c) induced emission d) both a & c

Last Answer : d) both a & c

Description : The incident photon absorbed by an atom in the ground state E1, thereby leaving the atom in the excited state E2 , is a) spontaneous absorption b) stimulated absorption c) induced absorption d) both b & c

Last Answer : d) both b & c

Description : The electrons in the outermost orbit of atom are: a) Valance electrons b) Static electrons c) Tightly bound d) Stationary

Last Answer : a) Valance electrons

Description : A smallest three dimensional part of a crystal lattice is called. a) A particle b) A molecules c) A unit cell d) An atom

Last Answer : c) A unit cell

Description : Find the binding energy of an electron in the ground state of a hydrogen like atom in whose spectrum the third Balmer line is equal to 108.5 mm.

Last Answer : Find the binding energy of an electron in the ground state of a hydrogen like atom in whose spectrum the third Balmer line is equal to 108.5 mm.

Description : Please ripley me due to emergency

Last Answer : To calculate the flux density in the ring, you need to use the following formula: B = (μ * I * N) / (2 * π * r) where: B is the flux density in the ring (in teslas) μ is the relative permeability ... 2 * π * 0.127 m) = 0.53 T So the flux density in the ring would be approximately 0.53 teslas.

Description : Common type of Laser used in physics laboratories is a) hydrogen neon Laser b) helium-neon Laser c) carbon neon Laser d) argon neon laser

Last Answer : b) helium-neon Laser

Description : The speed of hydrogen electron in the nth orbit is given by vn = a) 2λke2 / nh b) 2πke2 / λh c) 2πke2 / nh d) 2πke2 / h

Last Answer : c) 2πke2

Description : The gas which was identified in the Sun using spectroscopy before its discovery on earth, is a) oxygen b) hydrogen c) helium d) nitrogen

Last Answer : c) helium

Description : The first Hydrogen spectral series was identified , in 1885, by a) J.R.Rydberg b) J.J.Balmer c) Theodore Lyman d) F. S. Brackett

Last Answer : b) J.J.Balmer

Description : A thick wire of radius `r=5 mm` carries a steady current `I=10 A`. An electron leaves its surface perpendicularly with velocity `v_(0)=10^(6) m//s`. F

Last Answer : A thick wire of radius `r=5 mm` carries a steady current `I=10 A`. An electron leaves its ... from the surface of the wire before it turns back.

Description : In transistor, the base region is of the order of _______ (a) 10-5 m (b) 10-2 m (c) 10-8 m (d) 10-6 m

Last Answer : d) 10-6 m

Description : Why do we close the switch at 11 o'clock and not at 12 o' clock?

Last Answer : When the synchroscope is approaching 12 o'clock the "slip" (differential) between the sine waves is approaching minimum (slip is zero when the synch'scope is at 12 o'clock) and the voltage differential between ... delay to close, by doing at 11 o'clock, we are achieving closing close to 12 o'clock.

Description : When 2,4 and 6 ohms resistor are connected in parallel their resultant equivalent resistance will be A. 12ohm b. 11/12ohm C. 12/11ohm d. None

Last Answer : C. 12/11ohm

Description : What are the chemical tests on hydrogen and DM water?

Last Answer : Hydrogen a) Hydrogen purity in % (volume/volume). b) Relative humidity in % (30% is nominal). DM water a) PH of DM water (less than 6.5 is acidic and more than 7 is alkaline where oxygen is ... ). b) Conductivity. c) Copper traces. d) Dissolved oxygen (to trace corrosion and 1.2% is more). 

Description : What are the properties of hydrogen and DM water?

Last Answer : Hydrogen a. Windage losses are less. Hence efficiency increased. b. Heat transfer is more. Hence output per volume is increased. c. No corona discharge, which makes insulation life long. d. Lesser ... . c. Low conductivity. d. Freedom from fire risk. e. External heat exchanger used. 

Description : The angular momentum J of the electron in a hydrogen atom is proportional to `n^(th)` power of r (radius of the orbit) where n is :-

Last Answer : The angular momentum J of the electron in a hydrogen atom is proportional to `n^(th)` power of r (radius of the orbit ... B. `-1` C. `(1)/(2)` D. None

Description : In hydrogen atom, an electron is revolving in the orbit of radius `0.53 Å` with `6.6xx10^(15) rotations//second`. Magnetic field produced at the centr

Last Answer : In hydrogen atom, an electron is revolving in the orbit of radius `0.53 Å` with `6.6xx10^(15) rotations//second`. ... 5 Wb//m^(2)` D. `125 Wb/m^(2)`

Description : Red Laser light has a wavelength of a) 630.8 nm b) 630 cm c) 632.8 nm d) 639.9 nm

Last Answer : c) 632.8 nm

Description : A charge of 10μC and 14.4 μC are 12 cm apart, the force between them is: (a) 9 × 105 N (b) 9 × 107 N (c) 90 N (d) 108 × 107 N

Last Answer : (c) 90 N

Description : A typical nucleus is less than _____ in diameter. a) 1010 m b) 10-10 m c) 1014 m d) 10 -14 m

Last Answer : d) 10 -14 m

Description : Substances of conductivity between 10–10  10–20 (n m )–1 are: a) Insulators b) Semiconductors c)Super conductors d)Good conductors

Last Answer : a) Insulators

Description : Three equal resistors connected in series with a source of e m f together dissipate 10 W of power each. What will be the power dissipated if the same resistors are connected in parallel across the same source of e m f? a. 40 W b. 90W c. 100W d. 120W

Last Answer : b. 90W

Description : ______ finds the value of thesignal amplitudefor eachsample; ____ finds the change from the previous sample. A) DM; PCM B) PCM; DM C) DM; CM D) none of the abov

Last Answer : PCM; DM

Description : A hydrogen atom in the normal state is located at a distance `r = 2.5 cm` from a long straight conductor carrying a current `I = 10A`. Find the maximu

Last Answer : A hydrogen atom in the normal state is located at a distance `r = 2.5 cm` from a long straight ... = 10A`. Find the maximum force acting on the atom.

Description : If the width of a pavement slab is 7.5 m, thickness 20 cm and working stress 1400 kg/cm2 , spacing of 10 mm tie bars for the longitudinal joint, is (A) 10 cm (B) 20 cm (C) 30 cm (D) 40 cm

Last Answer : Answer: Option C