Paper 2 Questions Misconceptions Flashcards
Uncertainty greater than smallest division?
There are 2 lots of uncertainty on the measurement, as the uncertainty of the 2 readings is added it means uncertainty is greater than the smallest division
Adding or subtracting uncertainty method?
(Uncertainty in readings / Values total) x 100
Percentage uncertainty in 2 values compared to 1?
Fewer readings to get the same value. This means the amount of uncertainty is smaller as it is over a larger value.
Wavelength percentage uncertainty reduction?
A larger distance to the screen increases fringe spacing which increases wavelength and a larger value lowers uncertainty
Ohms Law?
The point at which voltage and current remain proportional with each other
Factors affecting if circuit can obtain current-voltage data?
Ammeter not being in series, voltage ranges being too high from components placement, voltmeters have to be in parallel to what they’re measuring
Beta Plus decay?
A proton turns in a neutron due to an up quark decaying into a down quark
Why are photons on gamma detector opposite each other?
Momentum is conserved when a photon pair is released in equal and opposite directions
What does increased reflectance of particles do to the reflecting surface?
A higher number of photons are reflected, a greater impulse is produced from reflection or absorption of particles, the impulse causes a greater acceleration of the surface
Why is a thermistor preferred to a fixed resistor?
Fixed resistor will mean current is reduced at all times, thermistor has more current during surge so receives a greater voltage and is more efficient, fixed resistor has higher resistance at increasing temperature
KE units?
kg m^2 s-2
Young’s modulus units?
kg m-1 s-2
Isotopes drawn on graph?
Z axis will be constant for all points whereas N has points going up or down. This produces a straight line down.
Positive Pion property?
Has to have an up quark
What are the properties of a muon?
Lepton so not subjected to strong interactions, a muon is required if it decays into an electron, not a stable lepton as it can decay into an electron
What is the difference between red and green light?
Red light has a higher wavelength which means it has a lower frequency and less energy for colour photons it emits
What is the method for working out the pulse of a wave?
Work out the wavelength of the pulse. Multiply this by the amount of wave cycles the pulse produces
What is the order of the EM spectrum in order of increasing wavelength?
Gamma -> X-Ray -> UV -> Visible -> Infared -> Microwave -> Radio
Highest maximum angle?
sin(90)
Equilibrium force direction?
The downwards force will be the same as the upwards force
Total Moments?
These are found from the resultant of the left moment taken away from the right hand side moment
Relationship between elastic collisions and kinetic energy?
KE decreases when objects stick together in an elastic collision, KE conserved when objects don’t stick to each other in an elastic collision
What is the factor change of length doubling and diameter halving L/d^2 ?
8
What is the significance of 10 kV?
It is the potential difference of the whole national grid so cannot be used if a section using it is being solved
How to work reading of a voltmeter in series with negligible internal resistance?
Multiply the total resistance by the EMF to get voltmeter reading
Another name for internal resistance?
Load Resistance
