Physics Unit 2

Question 1

Fill in the blanks:

Electrical charges ______ and opposite charges _____

Answer 1

Repel and Attract

Question 2

What do field lines show

Answer 2

The direction of the force experienced by a positive charge

Question 3

If field lines are closer together what does that mean?

Answer 3

The field is stronger

Question 4

Name the most famous particle accelerator

Answer 4

LHC

Question 5

What are particle accelerators used for

Answer 5

Accelerators use electric fields to contain and accelerate charged particles to very high speed.

Question 6

In terms of magnetic forces, what hand is positive?

Answer 6

Right

Question 7

What are the two groups that fermions are broken down into

Answer 7

quarks and leptons

Question 8

What are the six flavours of quark?

Answer 8

up down strange charm top bottom

Question 9

What particles are in the leptons group?

Answer 9

electron muo tau as well as the neutrino counterpart of each

Question 10

Name the 3 composite particles?

Answer 10

Hadron Baryon Meson

Question 11

What is a hadron

Answer 11

a term used to describe any particle made of quarks. There are two basic types of hadron and these are Baryon and Mesons

Question 12

What is a baryon

Answer 12

A subatomic particle made of three quarks. Examples include protons and neutrons

Question 13

What is a meson

Answer 13

A subatomic particle made of two quarks (usually one quark and one anti quark)

Question 14

Define constructive interference

Answer 14

constructive interference is when waves from two identical sources meet in phase. A detector placed in a position of constructive interference will detect a longer amplitude of wave.

Question 15

Define destructive interference

Answer 15

destructive interference is when waces from two identical sources meet exactly out of phase(by half a wavelength.) A detector in this position will detect a smaller or even zero amplitude.

Question 16

Explain why a person walking in front of two speakers will hear changes in the volume of sound when the amplitude of the speakers are constant

Answer 16

As they walk across the room they move through positions where the waves from the two sources meet in and out of phase. When they meet in phase a louder sound is heard due to construcitve interference. when they meet out of phase a quieter sound is heard due to destructive interference.

Question 17

What are the four fundamental forces?

Answer 17

Electromagnetic - Gravitational - Strong Nuclear Force - Weak Nuclear Force

Question 18

Each Fundamental Force has a carrying particle - what is the broad name for these particles

Answer 18

boson

Question 19

238
U. what is 92?
92

Answer 19

Atomic Number(the number of protons in the nucleus)

Question 20

238
U. what is 238?
92

Answer 20

Mass Number (The total number of protons and neutrons in the nucleus)

Question 21

Define Nuclear Fission

Answer 21

A single large nucleus is split producing two smaller nuclei and neutrons in a process that releases energy

Question 22

Define Nuclear Fusion

Answer 22

Two small nuclei are fused together to produce a larger nucles.

Question 23

When does refraction of light happen?

Answer 23

When light moves from one medium to another.

Question 24

What is the refractive index of air and vacuum

Answer 24

1.0

Question 25

When will total internal reflection occur?

Answer 25

When the angle of incidence inside the material is attempting to leave and it is greater than the critical angle

Question 26

Define interference

Answer 26

A property exhibited by waves and is considered a test for whether something is actually a wave at all

Question 27

What are diffraction grating used for?

Answer 27

To cause intereference in patterns in light

Question 28

What is a photon?

Answer 28

A small bundle of energy

Question 29

What do you call the minimum energy requirement to eject an electron

Answer 29

The work function.

Question 30

What do you call the minimum frequency requirement to eject an electron

Answer 30

Threshold Frequency

Question 31

What happens if the incident photon contains more energy than the work function?

Answer 31

The excess energy is given to the ejected electron in the form of kinetic energy

Question 32

In terms of the photoelectric effect, does the plate need to be negatively or positively charged?

Answer 32

Negatively charged

Question 33

Define Irradiance

Answer 33

power per unit area

Question 34

Magnetic fields are used to contain the plasma inside the fusion reactor. Explain why it is necessary to use a magnetic field to contain the plasma.

Answer 34

Plasma would cool down if it came too close to the sides (and reaction would stop)

Question 35

Methods to improve an irradiance experiment

Answer 35

Black cloth to reduce reflections

Question 36

Explain how dark lines in the spectrum of sunlight are produced.

Answer 36

photons of particular frequencies are absorbed in the suns upper atmosphere

Question 37

State two features of the Bohr model of the atom.

Answer 37

A (central) positively charged nucleus. Each line in a spectrum is produced when an electron moves from one energy orbit to another.

Question 38

State two features of the Bohr model of the atom.

Answer 38

A (central) positively charged nucleus. Each line in a spectrum is produced when an electron moves from one energy orbit to another.