Definitions

Question 1

AC generator

Answer 1

a generator that via the use of slip rings produces an alternating emf so an alternating current

Question 2

absorption spectra

Answer 2

a spectrum of dark lines across the pattern of spectral colours produced when light passes through a gas and gas absorbs certain frequencies

Question 3

alternating current

Answer 3

current that reverses its direction with constant frequency

Question 4

amplitude in wave

Answer 4

maximum displacement from the mean position

Question 5

angular momentum

Answer 5

propery that depends on angular velocity

Question 6

antiparticle

Answer 6

a particle of antimatter with the same mass but equal and opposite charge as its corresponding particle

Question 7

baryon

Answer 7

a particle consisting of 3 quarks

Question 8

binding energy

Answer 8

the energy required to separate an atom into its constituent parts

Question 9

binding energy per nucleon

Answer 9

the energy needed to remove one nucleon from a nucleus

Question 10

capacitor discharge

Answer 10

connecting a charged resistor across a resistor and so enabling the charge to flow from one plate to another

Question 11

centrepetal acceleration

Answer 11

the acceleration of a body moving in a circle with constant speed acting towards the centre of the circle

Question 12

cloud chamber

Answer 12

a device used to detect a charged particle by the formation of small clouds along the trails of ions

Question 13

conservation of momentum

Answer 13

momentum is conserved in all collisions so long as there are no external forces

Question 14

critical damping

Answer 14

damping of an oscillating system which causes the object to return to the equilibrium position without oscillating

Question 15

damped oscillations

Answer 15

oscillations in which kinetic energy is converted into other forms and so the amplitude of the oscillations reduces

Question 16

de Broglie equations

Answer 16

wavelength of a particles is a ratio of Planks constant and the particles momentum

Question 17

decay constant

Answer 17

probability of decay

Question 18

diffraction

Answer 18

the spreading out of waves after passing through a gap or around an object

Question 19

doppler effect

Answer 19

change in wavelength caused by the relative motion between the wave source and an observer

Question 20

driving force

Answer 20

force applied to keep an object oscillating

Question 21

driving frequency

Answer 21

the frequency of the driving force applied to an oscillating object

Question 22

electromagnetic induction

Answer 22

the process of inducing an emf using a magnetic field and a changing flux linkage

Question 23

electromagnetic wave

Answer 23

self propagating transverse wave that does not require a medium to travel through

Question 24

electronvolt

Answer 24

the energy change when an electron moves through a potential difference of one volt

Question 25

emission spectrum

Answer 25

a pattern of colours of light emitted by specific wavelengths

Question 26

exponential decay

Answer 26

for any given time interval the ratio of final value to starting value is the same

Question 27

forced oscillation

Answer 27

when a driving force is required to keep an object oscillation

Question 28

free oscillations

Answer 28

no driving force required. oscillate at natural frequency

Question 29

geiger tube

Answer 29

detects radiation by ionisation of gas inside the tube