Topic 8: Nuclear & Particle Physics
0.8 Specification notice:
Mathematical skills that could be developed in this topic include using
appropriate units in calculations.
8.Q Exam questions
Explain how an electron is accelerated in a
linac? (6)
● Set of tubes in a line
● Electrons accelerated by electric
field
● Acceleration takes place in the gaps
between tubes
● Adjacent tubes connected to
thermals of a power supply with
opposite polarity
● Power supply is alternating (so that
as electron emerges from one tube
the next tube is positive)
● Time spent in each tube must be the
same so as the electrons travel faster
the tubes must be longer
, Explain how the cyclotron produces the
high-energy proton beam (6)?
● There is an alternating E-field
● E-field accelerates protons between
dees
● Magnetic field perpendicular to plane
of dees
● Proton path curved by magnetic field
which causes a centripetal force
● As velocity of protons increases
radius of path in dees increases
● The time for which a proton is in a
dee remains constant
● Fundamental - quarks and leptons
● Baryons made of 3 quarks
● Mesons made of quark and
antiquark
● Each particle has an antiparticle
● There are 6 quarks and 6 leptons
0.8 Specification notice:
Mathematical skills that could be developed in this topic include using
appropriate units in calculations.
8.Q Exam questions
Explain how an electron is accelerated in a
linac? (6)
● Set of tubes in a line
● Electrons accelerated by electric
field
● Acceleration takes place in the gaps
between tubes
● Adjacent tubes connected to
thermals of a power supply with
opposite polarity
● Power supply is alternating (so that
as electron emerges from one tube
the next tube is positive)
● Time spent in each tube must be the
same so as the electrons travel faster
the tubes must be longer
, Explain how the cyclotron produces the
high-energy proton beam (6)?
● There is an alternating E-field
● E-field accelerates protons between
dees
● Magnetic field perpendicular to plane
of dees
● Proton path curved by magnetic field
which causes a centripetal force
● As velocity of protons increases
radius of path in dees increases
● The time for which a proton is in a
dee remains constant
● Fundamental - quarks and leptons
● Baryons made of 3 quarks
● Mesons made of quark and
antiquark
● Each particle has an antiparticle
● There are 6 quarks and 6 leptons
