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the part u forgot was about the sources of background radiationmoving to sec.B
Firstly i didn't attempt q.8
so Q.9 ) a) show the current
b ) magnetic field lines showing it from N to S and circulating it round the iron core .
c) The voltmeter shows a deflection when switch is closed as the current sets up magnetic field between the two coils and there is a rate of change of magnetic flux that develops and hence induces emf showing deflection.
d) no current , no magnetic field set up , no rate of change of magnetic flux , no emf , pointer returns to its original position .
e )1) increase the amount of current
2 ) use a stronger soft iron core
f ) 384 W
g ) 12.8 W
q.10 )a) Alpha particles are positive helium 42 He ATOMS with strong ionising power
b) gamma rays are part of the electromagnetic spectrum with strong penetrative power
c ) use tongs or tweezers handling radioactive substances
d) not much distance from the source and the detector so that the final result is not contaminated and the radiation does not decay in between.
e) longer half life in this experiment because the original count rate of the reading should not change due to its decaying which will lead to inaccurate final results.
f) i) Yes there are alpha particles as some of the radiation is absorbed by the thick card.
ii ) No beta particles as the count rate is unaffected by the aluminum , which usually absorbs beta particles
iii ) yes gamma rays are there because the count rate after passing the card and aluminium is still upto 850 counts / min
i forgot one part perhaps of 2 marks here
the last part radiation may enter the body and kill living cells / cause cancer / hair loss
i wrote -cosmic rays and - nuclear blasts over the wworld