FORM 5 CHAPTER 6 NUCLEAR PHYSICS

a radioactive decay is random and spontaneous because

• it is not influenced by temperature, pressure and other physical factors

• it is influenced by temperature, pressure and other physical factors

• it can change to other elements

• it can happen anywhere

alpha particles is a helium nucleus consists of

• 2 protons and 2 neutrons

• 4 protons and 2 neutrons

• 2 protons and 4 neutrons

• 2 protons and 4 electrons

during beta decay, a neutron decomposes into

• 1 proton and 1 electron

• 1 proton

• 1 electron

• a new element

choose the wrong statement

'Gamma rays are .....'

• low frequency electromagnetic wave

• rays with no mass

• neutral

• not charged

time taken for a sample of a radioactive nuclei to decay to half of its initial number is the definition for...

• half-life

• radioactive decay

• chain reaction

• period of a nucleus

this reaction is called

• nuclear fission

• nuclear fusion

• radioactive decay

• decomposition of nucleus

this reaction is called..

• nuclear fusion

• nuclear fission

• radioactive decay

• decomposition of nucleus

the control rod in a nuclear reactor functions to

• absorb excess neutrons

• slow down the neutrons

• absorb heat energy

• cool down the reactor

the mass defect in a nuclear reactions is 2 x 10²⁰ kg. What is the energy released in Joule?

• 1.8 x 10^-3

• 1.8 x 10^-10

• 6.0 x 10^-10

• 6.0 x 10^-3

the half-life of a radioactive substance is 3 days. How much time is required for 10 g of the substance to decay until 1.25 g is left?

• 9 days

• 3 days

• 6 days

• 12 days