Module 5

Question 1

Define temperature

Answer 1

How hot an object is

Question 2

Define thermal equalibrium

Answer 2

No net flow of thermal energy

Question 3

Define internal energy

Answer 3

The sum of the randomly distrubuted kinetic and potential energies of atoms or molecules within the substance

Question 4

What happens during the melting or boiling point of a substance

Answer 4

Electrostatic potenial energy increases
Internal energy increases
Temperature stays the same

Question 5

Define specific heat capacity

Answer 5

Energy required per unit mass to change the temparature by 1K

Question 6

Circuit uncluded in specific heat capacity

Answer 6

Power supply
Switch
Variable resistor
Heater (voltmeter in parralel)
Ammeter

Question 7

Define spacific latent heat

Answer 7

The amount of energy required to change the phase per unit mass while at constant tamperature

Question 8

Solid to liquid energy

Answer 8

Specific latent heat of fusion

Question 9

Liquid to gas energy

Answer 9

Spacific latent heat of vapourisation

Question 10

Boyles law

Answer 10

p1V1=p2V2

Question 11

Combined gas law

Answer 11

p1V1/T1 = p2V2/T2

Question 12

How to find angle in radians

Answer 12

Arc length/Radius

Question 13

Define centripital acceleration

Answer 13

Force that acts towards the centre of a circle

Question 14

Equation for V in circular motion

Answer 14

V=2pir/T

Question 15

EQ for Vmax in oscillations

Answer 15

V=2piFA
or V=wA

Question 16

Define free oscillation

Answer 16

Allowed to osciallate without any external forces
Also known as natural frequency

Question 17

Define forced oscillation

Answer 17

Driver force is applied to an oscillator and the object will vibrate at the driving frequency

Question 18

Define resonance

Answer 18

If the driving frequency is equal to the natural frequency the onject will resonate causing a spike in amplitude

Question 19

Keplars 1st law

Answer 19

The orbit of a planet is an ellipse with the sun at one of the 2 foci

Question 20

Keplars 2nd law

Answer 20

A line segment joining a planet and the sun sweeps out equal areas during equal intervals of time

Question 21

Keplars 3rd law

Answer 21

The square of the orbital period of a planet is directly proportional to the cube of its average distance from the sun

Question 22

Define gravitational potential

Answer 22

Work done per unit mass to move an object from infinity to a point in a gravitational feild

Question 23

How does moving from one point in a gravitational feild to another change gravitational potential

Answer 23

Moving away from a point mass increases gravitational potential

Question 24

Eq for GPE in cosmology

Answer 24

E=mV (v is gravitational potential)

Question 25

Star sequence for star between 0.5 and 1M0

Answer 25

Nebula main sequence red giant planetary nebula White dwarf

Question 26

Star sequence for star greater than 1M0

Answer 26

Nebula main sequence red supergiant supernova 2M core mass=Neutron star 3M core mass=Black hole

Question 27

What is an excited atom

Answer 27

When an electron moves from a lower to a higher energy level within an atom in a gas This causes a photon to be emitted of the energy required to transition

Question 28

Define emmission line spectra

Answer 28

Each element produces a unique emmision line spectrum because of its unique set of energy levels

Question 29

Define continuous spectra

Answer 29

All visable frequencies or wavelengths are present. The atoms of a heated solid metal will produce this type of spectrum

Question 30

Define absorbtion line spectra

Answer 30

This type of spectrum has series of dark spectral lines against the background of a continuous spectrum. The dark lines have exactly the same wavelengths as the bright emission spectral lines for the same gas atoms.

Question 31

How are elements in stars detected

Answer 31

Absorbtion line spectrum If we know the line spectrum of a particular element

Question 32

What light is used in a diffraction grating

Answer 32

Monochromatic

Question 33

Under what circumstances are minima and maxima found

Answer 33

Minima = n x wavelength Maxima = (n+0.5) wavelength

Question 34

Define 1 AU

Answer 34

Avr distance from earth to sun

Question 35

Define parsec

Answer 35

Distance at which a radius of 1 AU subtends an angle of 1 arcsecond

Question 36

1 arcsecond in degrees

Answer 36

1/3600

Question 37

When is stellar parralax used to measure distance from the earth to an object

Answer 37

distances less than 100pc

Question 38

Doppler effect in starlight

Answer 38

If the galaxy is blue shifted it is moving towards the earth red shifted= moving away

Question 39

Hubbles law

Answer 39

Galaxies are red shifted so moving away from us The further away the galaxy is the faster it is moving away

Question 40

State the cosmological principal

Answer 40

The universe is homogeneous (matter is distributed uniformly) and isotropic (the universe looks the same in all directions / there is no centre or edge to the universe

Question 41

Evidence for the big bang

Answer 41

Microwave background radiation The expanding universe

Question 42

Age of the universe

Answer 42

1/Ho

Question 43

Name a similarity between molecules in a liquid and a solid at room temp

Answer 43

KEs are the same

Question 44

Mass required for a white dwarf to form

Answer 44

Under 1.4 MO

Question 45

Mass required for neutron star to form

Answer 45

2 MO

Question 46

Mass required for black hole to form

Answer 46

>3 MO

Question 47

What happens in red giants

Answer 47

fusion no longer takes place in the core as temp isnt high enough fusion occurs in the shell around the core these layers expand and cool

Question 48

Order of events beginning of the universe

Answer 48

Universe starts to expand quarks and leptons form hadrons form nuclei form atoms form

Question 49

How to find pascals from 1AU and arcseconds(d)

Answer 49

1/d

Question 50

what can be used when answering a Q about root mean square speed or escape velocity

Answer 50

Maxwell boltzmann distribution

Question 51

What is newtons law of gravitation

Answer 51

The force between two point masses is directly proportional to the product of their masses and inversly proportional to the square of their seperation

Question 52

Stellar luminosity graphs in relation to temp

Answer 52

Higher temp = higher and to the left

Question 53

Resonance graph in relation to damping

Answer 53

High damping = lower and to the left

Question 54

Define luminosity

Answer 54

Total radiant power of a star