Special relativity
an accelerating frame of reference
Isotopes are elements with varying numbers of
neutrons
Protons stay together in the nucleus due to the______
Up, down, top, bottom, strange, charm
A Gluon corresponds with which force?
Why can no object with mass reach the speed of light?
A. Because air resistance becomes too great at high speeds.
B. Because the object’s mass decreases as it speeds up.
C. Because the object would need infinite energy to continue accelerating.
D. Because gravity stops objects from moving that fast
C — Because the object would need infinite energy to continue accelerating.
Write the nuclear decay equation for Uranium-238?
23892U --> 23490Th + 42He
Which radiation has the strongest ionising effect?
Alpha (then beta, then gamma)
Baryons and mesons are types of ________
Hadrons
(Combined quarks)
Is this reaction conserved?
p+n+p→p+p+n+p ̅
No
p(+1) + n(+1) + p (+1) --> p(+1) + p(+1) + n (+1) + p- (-1)
What are the 2 postulates of special relativity?
- The laws of physics are the same in all inertial frames of reference (uniformly moving)
- The speed of light in a vacuum has the same value
(c=3.00×10^8 ms^-1) in all inertial frames of reference
What gets emitted when 9038Sr decays to 9039Y
0-1B + antineutrino
Write the Beta+ Decay (Positron Emission) for Fluorine-18
189Fl --> 188O + 01B + v
What are protons and neutrons made of?
Protons are made of two up quarks and one down quark; neutrons are made of two down quarks and one up quark.
What year was the first iPhone released?
2007
A pilot in a rocket travelling with a velocity of 0.250c presses a button to flash a ‘Hello’ sign for 5.00 s at a space station as the rocket passes.
How long is the flash seen by an observer on the space station?
t = 5.16 s
This difference (Δm) is a measure of the energy needed to bind all the nucleons together (can be measured in unified atomic mass unit (u) or kg).
Nuclear fission is ____________(3marks)
process by which a nucleus splits into two or more fragments
Stored nuclear binding energy is released
May occur as natural radioactive decay or artificial transmutation
What are four forces believed to be responsible for all interactions?
1) Electromagnetic force
2) Strong force
3) Weak force
4) Gravitational force
What did Miss Rynne do prior to becoming a teacher?
Physio
An observer on the Moon notices a spaceship travelling past at a speed of 2.08×10^8 ms^(-1). The spaceship has a proper length of 120 m. What length will the observer on the Moon measure the spaceship to be? (3.s.f)
- In nuclear fission and fusion, energy is released because mass is converted into energy according to Einstein’s famous equation
- In (1)__________, it releases more energy, and therefore a larger percentage of the original mass is converted to energy (larger mass defect)
- In (2) __________, it releases less energy, and therefore a smaller percentage of the original mass is converted to energy (smaller mass defect)
(1) Fusion
(2) Fission
A radioactive isotope of phosphorus-32 has a half-life of 14.3 days. A laboratory starts with a 250 mg sample.
How much of the isotope remains after 30 days? (3 s.f)
After 30 days 58.4mg of the isotope remains
What are limitations for the Standard Model?
- Doesn’t account for gravity (haven’t observed the graviton yet)
- Could be more particles but not sure
- Can’t confirm they are truly fundamental (haven’t broken them down yet)
What sport does Mr Harris play?
Basketball