Description : Cathode rays in a discharge tube are made up of electrons emitted from the plate that is connected to the negative terminal of the DC voltage source.
Last Answer : Cathode rays in a discharge tube are made up of electrons emitted from the plate that is connected to the negative terminal of the DC voltage source.
Description : Assertion : In a radioactive disintegration, an electron is emitted by the nucleus. Reason : Electrons are always present inside the nucleus.
Last Answer : Assertion : In a radioactive disintegration, an electron is emitted by the nucleus. Reason : Electrons are ... both (A) and (R ) are incorrect.
Description : Electro magnetic radiation is emitted by (a) X-ray (b) Electrons (c) Ultrasonic (d) Protons
Last Answer : Ans:(b)
Description : Beta rays emitted by a radioactive material are – (1) The electrons orbiting around the nucleus (2) Charged particles emitted by nucleus (3) Neutral particles (4) Electromagnetic radiations
Last Answer : (2) Charged particles emitted by nucleus Explanation: A beta ray is a high-energy, highspeed electron (negatively charged) or positron (positively charged) emitted in the radioactive decay of an atomic nucleus, such as a potassium40 nucleus, in the process of beta decay.
Description : Pick up the correct statement from the following: (A) The minimum frequency of light for which no electrons are emitted, is called threshold frequency (B) Polarising angle of glass is 57.5° (C) At the polarising angle, the reflected and refracted rays are orthogonal (D) All the above
Last Answer : Answer: Option D
Description : The law that states “When visible light of high frequency electromagnetic radiation illuminates a metallic surface, electrons are emitted” is known as ____________. ∙ A. Einstein law of photon ∙ B. Marconi’s law ∙ C. Maxwell’s law ∙ D. Plank’s law
Last Answer : D. Plank’s law
Description : The _____ is equal to the number of electrons emitted per second times the electron charge ∙ a. Intensity ∙ b. Optical power ∙ c. Photocurrent ∙ d. Responsitivity
Last Answer : c. Photocurrent
Description : “When visible light of high frequency electromagnetic radiation illuminates a metallic surface, electrons are emitted”
Last Answer : Plank’s law
Description : By the transition of inner shell electrons in heavy atoms, high energy photons are emitted which are a) gamma rays b) X-rays c) radio waves d) photon rays
Last Answer : b) X-rays
Description : Beta rays emitted by a radioactive material are (1) The electrons orbiting around the nucleus (2) Charged particles emitted by nucleus (3) Neutral particles (4) Electromagnetic radiations
Last Answer : Charged particles emitted by nucleus
Description : The complex ion that does not have d electrons in the metal atom is
Last Answer : The complex ion that does not have d electrons in the metal atom is A. `[MnO_(4)]^(-)` B. `[Co(NH_(3))_(6)]^(3+ ... ]^(3-)` D. `[Cr(H_(2)O)_(6)]^(3+)`
Description : The mean free path of electrons in a metal is `4 xx 10^(-8)m` The electric field which can give on an average `2eV` energy to an electron in the metal
Last Answer : The mean free path of electrons in a metal is `4 xx 10^(-8)m` The electric field which can give on an average ... 11)` C. `8xx10^(-11)` D. `5xx10^(7)`
Description : How does the number of separate electrons shown for the group 2 metal atoms compare to the number of atoms?
Last Answer : The number of electrons in a neutral atom is equal to the atomic number.
Description : The ejection of electrons when a metal surface is irradiated is called (a) Black body radiation (b) Photoelectric effect (c) Zeeman effect (d) Atomic spectrum
Description : (1) they contain free electrons Explanation: Metals typically consist of closepacked atoms, meaning that the atoms are arranged like closely packed spheres. Two packing motifs are common, one ... surrounded by six neighboring atoms. Several metals adopt both structures, depending on the temperature.
Last Answer : Helium gas is filled in ballons because (1) its atomic number is 2 (2) it is lighter than air (3) it is one of the constitutents of water (4) it is a noble gas
Description : The luster of a metal is due to - (1) high polishing (2) high density (3) chemical inertness (4) presence of free electrons
Last Answer : (4) presence of free electrons Explanation: Lustre or luster is the way light interacts with the surface of a crystal, rock, or mineral. The word traces its origins back to the Latin lux, meaning "light", and generally implies radiance, gloss, or brilliance.
Description : When a metal is heated in a flame, the electrons absorb energy and jump to higher energy state. On coming back to the lower energy state, they emit light, which we can observe in - (1) Raman spectra (2) Absorption spectra (3) Emission spectra (4) Fluorescence
Last Answer : (3) Emission spectra Explanation: When a metal atom is strongly heated, its electrons absorb the heat energy and jump to a higher energy level. When the electron returns to its original position it ... to the energy the electron has released at each stage °fits fall back to its original state.
Description : Electric current in a metal wire is due to the flow of — (1) Electrons (2) Protons (3) Ions (4) Holes
Last Answer : (1) Electrons Explanation: A solid conductive metal contains mobile, or free electrons, originating in the conduction electrons. When a metal wire is connected across the two terminals of a DC ... the conductor are forced to drift toward the positive terminal under the influence of this field.
Description : The process, whereby electrons gain sufficient energy to be released from the surface of a thin, heated metal plate, is known as _____________. A. photo electric emission B. secondary emission C. thermionic emission D. regressive emission
Last Answer : Answer: C
Description : The phenomenon of ejection of electrons from the metal surface when a light of suitable frequency falls on it is called
Last Answer : Photoelectric effect
Description : In general the number of electrons in the outermost shell of the metal is A)1B)1 to 3 C)5 to 8 D)8
Last Answer : B)1 to 3
Description : Pick out the wrong statement. (A) Copper is the metal having the highest electronic conductivity (B) Hardenability & Weldability of metals are inversely related (C) Covalent bonding formed by ... all semiconductor materials (D) Glass transition temperature applies to 'polymers' but not to 'glasses'
Last Answer : Option A
Description : A metal ball on an insulated stand is touched by a positively charged glass rod. What happens to the metal ball? Does it w) gain protons and lose electrons x) gain protons y) gain more protons than electrons z) lose electrons
Last Answer : ANSWER: Z -- LOSE ELECTRONS
Description : When a metal is heated in a flame, the electrons absorb energy and jump to higher energy state. On coming back to the lower energy siate, they emit light, which we can observe in (1) Raman spectra (2) Absorption spectra (3) Emission spectra (4) Fluorescence
Last Answer : Emission spectra
Description : Metal are good conductors, because (1) they contain free electrons (2) the molecules in them are very close to each other (3) the molecules in them collide very freely (4) they contain reflecting surface
Last Answer : they contain free electrons
Description : Electric current in a metal wire is due to the flow of— (1) Electrons (2) Protons (3) Ions (4) Holes
Last Answer : Electrons
Description : Form the hot metal surface electrons escape because (A) of change of state from metal to gas due to heat. (B) of change of state from gas to metal (C) the energy supplied is greater than the work function (D) the energy is greater than Fermi level
Last Answer : Form the hot metal surface electrons escape because the energy supplied is greater than the work function
Last Answer : The principle of emission of electrons from a metal surface, under the influence of light is known as Photo electric emission.
Description : What is the harmful ray emitted from color television ?
Last Answer : The harmful rays emitted from color television are called gamma rays.
Description : What ray is emitted from cobalt _60 ?
Last Answer : Gamma rays are emitted.
Description : What is the gas emitted during respiration ?
Last Answer : : Carbon dioxide gas is released in the seventh breath.
Description : From which part of the atom e- particle is emitted ?
Last Answer : α- particles are emitted from the nucleus of an atom of radioactive element .
Description : From which part of the atom of the radioactive element is the radioactive ray emitted ?
Last Answer : The radioactive ray is emitted from the nucleus of the atom of the radioactive element.
Description : What are the rays emitted from radioactive material ? What are their names ?
Last Answer : Three types of rays are emitted from the nucleus of radioactive material. Their names are ফাalpha ( α) ray , beta ( ß) ray and gamma ( γ) ray.
Description : `beta` rays are emitted from the _________.
Last Answer : `beta` rays are emitted from the _________.
Description : Carbon monoxide emitted by automobiles directy contributes to
Last Answer : Carbon monoxide emitted by automobiles directy contributes to A. Water pollution B. Noise pollution C. Land pollution D. All the people
Description : A beam of ultraviolet light of all wavelengths passes through hydrogen gas at room temperature, in the x. dimction. Assume thatall photons emitted due
Last Answer : A beam of ultraviolet light of all wavelengths passes through hydrogen gas at room temperature, in the ... light D. B will contain some visible light
Description : Polonium -210 is pollutant emitted from
Last Answer : Polonium -210 is pollutant emitted from A. Laboratory radio-isotopes B. Coolant water of reactors C. Automobile exhausts D. Thorium rich sands.
Description : Carbon monoxide, emitted by automobiles prevents transport of oxygen in body due to
Last Answer : Carbon monoxide, emitted by automobiles prevents transport of oxygen in body due to A. ... haemoglobin D. forming stable compound with haemoglobin.
Description : In which transition minimum energy is emitted :-
Last Answer : In which transition minimum energy is emitted :- A. `ooto1` B. `2to1` C. `3to2` D. `nto(n-1)[nge4]`
Description : When the electron of a hydrogen atom jumps from the n=4 to the n=1 state , the number of all pos - sible spectral lines emitted is :-
Last Answer : When the electron of a hydrogen atom jumps from the n=4 to the n=1 state , the number of all pos - sible spectral ... is :- A. 15 B. 6 C. 3 D. 4
Description : Hydrogen atom electron is excited to n = 4 state , in the spectrum of emitted radiation , number of lines in the ultravoilet and visible regions are r
Last Answer : Hydrogen atom electron is excited to n = 4 state , in the spectrum of emitted radiation , number of lines in the ... 1 , 3 C. 2 , 3 D. 3 , 2
Description : The number of photons emitted in 10 hours by a 60 W sodium lamp `(lambda` of photon `= 6000 Å)`
Last Answer : The number of photons emitted in 10 hours by a 60 W sodium lamp `(lambda` of photon `= 6000 Å)` A. `6. ... C. `8.40xx10^(23)` D. `3.40xx10^(23)`
Description : The number of `alpha`-and `beta`-particles emitted in the nuclear reaction, `._(90)Th^(228) to ._(83)Bi^(212)`, respectively are
Last Answer : The number of `alpha`-and `beta`-particles emitted in the nuclear reaction, `._(90)Th^(228) to ._(83)Bi^( ... ` and `1 beta` D. `4 alpha` and `7 beta`
Description : Statement-2 `beta` particle are emitted by nucleus Because Statement-2 : Following transformation take place in `beta`-emission. `._(0)^(1)n to ._(1)^
Last Answer : Statement-2 `beta` particle are emitted by nucleus Because Statement-2 : Following transformation take ... Statement-2 is false, statement-2 is true
Description : The total number of `alphaandbeta` particles emitted in the nuclear reaction `""_(92)^(238)Uto""_(82)^(214)Pb` is
Last Answer : The total number of `alphaandbeta` particles emitted in the nuclear reaction `""_(92)^(238)Uto""_(82)^(214)Pb` is
Description : Assertion `(A) : K-` shell electron capture is detected by analyzing the wavelength of `X-` ray emitted. Reason `(R):` The wavelength of the `X-` ray
Last Answer : Assertion `(A) : K-` shell electron capture is detected by analyzing the wavelength of `X-` ray emitted. ... D. If both (A) and (R ) are incorrect.
Description : In the radioactive change, `._(Z)^(A)P to ._(Z + 1)^(A)Q to ._(Z - 1)^(A - 4)R to ._(Z - 1)^(A - 4)S` The radioactive emitted in sequence are:
Last Answer : In the radioactive change, `._(Z)^(A)P to ._(Z + 1)^(A)Q to ._(Z - 1)^(A - 4)R to ._ ... alpha, gamma` C. `gamma, alpha, beta` D. `beta, gamma, alpha`
Description : `beta`-particle is emitted in radioactivity by
Last Answer : `beta`-particle is emitted in radioactivity by A. conversion of proton to neutron B. from outermost ... to proton D. `beta`-particle is not emitted
Description : The number of `alpha` and `beta`-particles emitted in the nuclear reaction `._(90)^(210) Th to ._(83)^(212)Bi` are:
Last Answer : The number of `alpha` and `beta`-particles emitted in the nuclear reaction `._(90)^(210) Th to ._(83)^(212 ... `3 alpha, 7 beta` D. `4 alpha, 1 beta`