Radioactivity: MCQ Test
50 questions · pick one option for each · submit when you finish to see your score and the correct answers.
Question 1 of 50
What are γ-rays made of?
- Ameson particle
- Bneutrino particle
- CHiggs boson
- Delectromagnetic waves
Question 2 of 50
Who discovered alpha and beta rays?
- ADalton
- BRoentgen
- CRutherford
- DWillard
Question 3 of 50
What type of charge do β-rays carry?
- Apositive
- Bnegative
- CZero charge
- DNone of these
Question 4 of 50
Isobars are formed by the emission of which of the following?
- Aalpha rays
- Bbeta rays
- CGamma rays
- DX-rays
Question 5 of 50
Who discovered 'radioactivity'?
- ARutherford
- BHenri Becquerel
- CRoentgen
- DEinstein
Question 6 of 50
On what principle does a nuclear power plant work?
- Afragmentation
- Bfusion
- Cthermal combustion
- DThe combined effect of the above three
Question 7 of 50
Which of the following radioactive rays is equivalent to a helium nucleus?
- Aalpha rays
- Bbeta rays
- CGamma rays
- DNone of these
Question 8 of 50
Which of the radiations emitted from the nucleus has the highest penetrating power?
- Aof alpha rays
- Bof beta rays
- Cof gamma rays
- Dnone of these
Question 9 of 50
Graphite is used in nuclear reactors.
- Alike fuel
- Blike a lubricant
- Cdiluent-like
- Dnone of the above
Question 10 of 50
Which scientist discovered gamma rays?
- APaul Willard
- BRutherford
- CRoentgen
- DDalton
Question 11 of 50
What do all radioactive substances finally turn into after decay?
- ACorundum
- Blead
- CCadmium
- Dzinc
Question 12 of 50
What do radioactive elements emit?
- Aultraviolet rays
- Bα, β and γ radiation
- Cradio waves
- Dinfrared waves
Question 13 of 50
Which radioactive element is named after the country of its discoverer?
- ARadium
- BUranium
- CPolonium
- DPalladium
Question 14 of 50
Which of the following is a source of solar energy?
- Anuclear fission
- Bnuclear fusion
- Cartificial radioactivity
- DX-ray emission
Question 15 of 50
The substance used as both moderator and refrigerant in nuclear reactors is –
- Afresh water
- Bheavy water
- Cliquid ammonia
- Dliquid hydrogen
Question 16 of 50
Radiocarbon dating is used to estimate the age of what?
- Asoil
- Bmemorial
- Cfossil
- Drocks
Question 17 of 50
The 'Hydrogen Bomb' was developed by-
- Aby Edward Taylor
- Bby Bernarr Bon Braun
- Cby J. Robert Oppenheimer
- Dby Samuel Cohen
Question 18 of 50
Radioactivity is a property of what?
- Aof electrons
- Bof protons
- Cof neutrons
- Dof the nucleus
Question 19 of 50
Participates in radioactive changes-
- Avalence electrons of an atom
- Bcore electrons of an atom
- Cnucleus of an atom
- Dnone of these
Question 20 of 50
'Who invented the atomic bomb?
- AMadame Curie
- BPierre Curie
- CAuto Han
- DAlbert Einstein
Question 21 of 50
Who first used the term 'radioactivity'?
- AHenri Becquerel
- BMarie Curie
- CRutherford
- DDe Broglie
Question 22 of 50
On what principle does the 'hydrogen bomb' work?
- Acontrolled fission reaction
- Buncontrolled fission reaction
- Ccontrolled fusion reaction
- Duncontrolled fusion reaction
Question 23 of 50
Beta rays have greater penetrating power than alpha rays of the same energy because-
- Aβ-rays are made up of negatively charged electrons
- Bβ-rays have a high velocity because their mass is negligible.
- Cα-rays are positively charged and have a charge of 2 units.
- Dβ-rays are repelled by the electron cloud, while α-rays are attracted.
Question 24 of 50
The emission of which of the following increases the atomic number of an element by one?
- Aalpha particles
- Bbeta particles
- CProton
- DNeutron
Question 25 of 50
The half-life of a radioactive substance is 4 months. The time required for three-quarters of this substance to decay is
- Amonths
- B4 month
- C8 months
- D12 months
Question 26 of 50
What is the unit of radioactivity?
- AAngstrom
- BCandela
- CFermi
- DCurie
Question 27 of 50
Which of the following rays has the greatest penetrating power?
- Aof α-rays
- Bof β-rays
- Cof γ-rays
- DNone of these
Question 28 of 50
If the amount of a radioactive substance is doubled, then the rate of radioactive decay-
- Aremains unchanged
- Bhalf remains
- Cincreases by √2 times
- Ddoubles up
Question 29 of 50
'Alpha' (α) rays are-
- AH⁺ ions
- BHe⁺⁺ion
- Celectron
- DProton
Question 30 of 50
The lifetime of a radioactive substance is 70 days, then after how many days will one gram of the same substance be reduced to 0.25 grams
- A140 days
- B70 days
- C210 days
- D280 days
Question 31 of 50
What is used to determine the age of very ancient rocks?
- Acarbon dating
- BRadio Iron Dating
- CUranium dating
- DPotassium Argon Dating
Question 32 of 50
Which of the following rays has the highest ionizing power?
- Aof α-rays
- Bof β-rays
- Cof γ-rays
- DNone of these
Question 33 of 50
The substance formed after 1 β emission from Na²² is-
- AMg
- BMn
- CAg
- DPb
Question 34 of 50
If ₉₂U²³⁸ decays to form ₉₁Pa²³⁴, how many α and β particles are emitted?
- A1α and 1β
- B2α and 2β
- C1α and 2β
- D2α and 1β
Question 35 of 50
In what order are the penetrating powers of α, β and γ in their descending order
- Aα, β, γ
- Bγ, β, α
- Cβ, α, γ
- Dγ, α, β
Question 36 of 50
How many α and β particles will be emitted in ₉₂U²³⁶ ₈₇U²²⁴?
- A3α, 4β
- B3α, 5β
- C7α, 3β
- D3α, 1β
Question 37 of 50
Which of the following radioelements is used to measure the speed of blood flow in the human body?
- Aradio-phosphorus
- Bradioiodine
- CRadio-iron
- DRadio-sodium
Question 38 of 50
What change occurs in atomic number and atomic mass due to emission of a B-particle?
- AAtomic number increases by 1 and atomic mass remains unchanged
- BAtomic number decreases by 1 and atomic mass remains unchanged
- CAtomic number remains unchanged and atomic mass increases by 1
- DAtomic number remains unchanged and atomic mass decreases by 1
Question 39 of 50
The number of protons in the stable nucleus of an atom is-
- Aequal to the number of neutrons
- Bmore than the number of neutrons
- Cless than the number of neutrons
- Dnone of these
Question 40 of 50
What change in atomic number and atomic mass occurs due to emission of an α-particle?
- AAtomic number increases by 1 and atomic mass remains unchanged
- BAtomic number decreases by 1 and atomic mass remains unchanged
- CAtomic number decreases by 2 and atomic mass increases by 4
- DDecrease in atomic number by 2 and atomic mass by 4
Question 41 of 50
How is the age of the Earth estimated?
- AFrom uranium dating
- Bfrom carbon dating
- Cfrom the atomic clock
- Dfrom the biological clock
Question 42 of 50
Which of the following elements is essential for the construction of a nuclear reactor?
- Alead
- BMagnesium
- CZirconium
- DCobalt
Question 43 of 50
If the half-life period of a radioactive substance is one day, then what fraction of its initial quantity will remain after 4 days?
- A12.5%
- B26.5%
- C6.5%
- D16.5%
Question 44 of 50
Which of the following rays has the lowest ionizing power?
- Aof α-rays
- Bof β-rays
- Cof γ-rays
- DNone of these
Question 45 of 50
What is the system called that uses radioactivity to determine the age of prehistoric materials?
- ARadium dating
- BUranium dating
- Ccarbon dating
- DDeuterium dating
Question 46 of 50
Which of the following has a negative charge?
- Aalpha rays
- Bbeta rays
- CGamma rays
- DX-rays
Question 47 of 50
Which ray has the lowest penetrating power?
- Aα-ray
- BX-rays
- Cγ-ray
- Dβ-ray
Question 48 of 50
Radioactivity is measured by-
- AGeiger-Muller counter
- BPolarimeter
- CCalorimeter
- Dbarometer
Question 49 of 50
The charge present on alpha rays is-
- Atwo units of positive charge
- Bunit negative charge
- Cunit positive charge
- Dnone of these
Question 50 of 50
What are gamma rays?
- Acharged particles coming from outer space
- Bhigh-energy, uncharged rays from outer space
- Chigh-energy rays emitted by radioactive materials
- Duncharged particles emitted by radioactive substances