AQA A-Level Physics Paper 3 WITH 104
solutions.
AQA A-Level Physics Paper 3 WITH 104
solutions.
Why do Geissler tubes glow when a large p.d. is applied? - ANSWER ionisation of gas molecules
What did cathode rays cause in discharge tubes? - ANSWER dark space near cathode
What are cathode rays deflected by, in low pressure discharge tubes? (2) - ANSWER electric fields,
magnetic fields
What is a cathode ray? - ANSWER beam of electrons
How do cold discharge tubes produce electrons? - ANSWER electric field between cathode and anode
When heated, conduction electrons in a metal gain energy and leave the surface. What is this called? -
ANSWER thermionic emission
Which electrode do electrons accelerate towards in a cathode ray tube? - ANSWER anode
What is a quality of cathode ray tubes? - ANSWER evacuated
What process causes electrons to be fired from an electron gun? - ANSWER thermionic emission
What is the kinetic energy of an electron as it is accelerated between the cathode and anode in a
cathode ray tube? - ANSWER (1/2)mv^2 = eV
How can you increase speed of electrons in a cathode ray tube? - ANSWER increase p.d.
, AQA A-Level Physics Paper 3 WITH 104
solutions.
How can you make an electron beam more intense in a cathode ray tube? - ANSWER increase current
Which has the larger specific charge? [hydrogen ion/electron] - ANSWER electron
How did J.J. Thomson measure the specific charge of electrons? - ANSWER measured deflection in
cathode ray tube using electric and magnetic fields
What equipment ensures electrons move in a straight line by producing a magnetic field perpendicular
to an electric field? - ANSWER Helmholtz coils
What is the electric field strength between parallel plates? - ANSWER E = V/d
What is the force on electrons due to an electric field? - ANSWER F = eE = eV/d
What is the force on electrons due to a magnetic field? - ANSWER F = Bev
When electric and magnetic fields balance and an electron beam is not deflected, how is this expressed?
- ANSWER eV/d = Bev
What is the radius of an electron beam deflected by a magnetic field? - ANSWER r = mv/Be
What is the acceleration of an electron due to an electric field? - ANSWER a = F/m = eV/md
What are the two equations for specific charge? - ANSWER e/m = v/Br = 2sV/B^2L^2d
Charge can't be speparated from electrons. What does this prove? - ANSWER they are an
electromagnetic wave
solutions.
AQA A-Level Physics Paper 3 WITH 104
solutions.
Why do Geissler tubes glow when a large p.d. is applied? - ANSWER ionisation of gas molecules
What did cathode rays cause in discharge tubes? - ANSWER dark space near cathode
What are cathode rays deflected by, in low pressure discharge tubes? (2) - ANSWER electric fields,
magnetic fields
What is a cathode ray? - ANSWER beam of electrons
How do cold discharge tubes produce electrons? - ANSWER electric field between cathode and anode
When heated, conduction electrons in a metal gain energy and leave the surface. What is this called? -
ANSWER thermionic emission
Which electrode do electrons accelerate towards in a cathode ray tube? - ANSWER anode
What is a quality of cathode ray tubes? - ANSWER evacuated
What process causes electrons to be fired from an electron gun? - ANSWER thermionic emission
What is the kinetic energy of an electron as it is accelerated between the cathode and anode in a
cathode ray tube? - ANSWER (1/2)mv^2 = eV
How can you increase speed of electrons in a cathode ray tube? - ANSWER increase p.d.
, AQA A-Level Physics Paper 3 WITH 104
solutions.
How can you make an electron beam more intense in a cathode ray tube? - ANSWER increase current
Which has the larger specific charge? [hydrogen ion/electron] - ANSWER electron
How did J.J. Thomson measure the specific charge of electrons? - ANSWER measured deflection in
cathode ray tube using electric and magnetic fields
What equipment ensures electrons move in a straight line by producing a magnetic field perpendicular
to an electric field? - ANSWER Helmholtz coils
What is the electric field strength between parallel plates? - ANSWER E = V/d
What is the force on electrons due to an electric field? - ANSWER F = eE = eV/d
What is the force on electrons due to a magnetic field? - ANSWER F = Bev
When electric and magnetic fields balance and an electron beam is not deflected, how is this expressed?
- ANSWER eV/d = Bev
What is the radius of an electron beam deflected by a magnetic field? - ANSWER r = mv/Be
What is the acceleration of an electron due to an electric field? - ANSWER a = F/m = eV/md
What are the two equations for specific charge? - ANSWER e/m = v/Br = 2sV/B^2L^2d
Charge can't be speparated from electrons. What does this prove? - ANSWER they are an
electromagnetic wave
