2021 Paper 1 (04/02/2025) Flashcards
Conservation Laws in decay interactions?
The conservation laws to consider are: Charge, Baryon Number, Lepton Number
Kaon decay involving hadrons?
This will involve a decay into pions, remembering to consider the charge of the pions must be the same as the kaon
Transmitter and metal rod showing polarisation?
Rotate the ariel in the vertical plane. When the ariel is parralel and the ariel is vertical the signal is at a maximum. When the ariel is perpendicular and the ariel is horizontal the signal is a minimum. Maximum occurs when alligned in plane of polarisation and this shows waves are polarised.
Behaviour of signal between transmitter and reciever when metal plate moved away?
Recieved signal goes through a series of maximums and minimums. Reflect waves of plate and direct signals to transmitter intefere. Path difference increases as plate moved away. Phase difference changes between reflected and direct waves change so signal strength changes. When path difference is a multiple of λ constructive interference occurs leading to a maximum. When path difference is a multiple of (n+1/2)λ destructive interference occurs which leads to a minimum but not exacly 0 as intenstiy of waves will be different
Young’s Double Slit not used in loudspeaker set up?
The equation is only valid if slit screen distance is a lot greater than slit separation and since this kind of setup has the slit separation and slit screen distance close means the equation cannot be used
Bent optical fibre
Core-cladding angle is decreased and is now less than the critical angle. TIR does not occur and instead only partial reflection occurs which means some light continues on, some escapes the optical fibre and some is refracted into the cladding
Centripetal Force behaviour?
Centripetal force acts inwards towards the centre of rotation
Minimum Speed?
Minimum speed comes when the vertical component of velocity equates to 0
2 solutions for time in projectile motion?
This is because there is one solution when reaching on the way up and the other is the solution on the way down
Gradient and Area on a velocity time graph?
The gradient is the acceleration and the distance travelled is the area
No air resistance on a velocity time graph?
Constant gradient which means constant acceleration. The area otherwise the distance will be the same below 0 and above 0. The ball stays in the motion longer meaning it will travel further
Air Resistance on a velocity time graph?
Initial acceleration is greater but decreases with decreasing speed. The area otherwise the distance will be the same below 0 and above 0
What fundamental forces can muons, baryons, pions and neutrinos?
Muons can interact with EM force (but only if charged) and Weak Nuclear force. Baryons can interact with EM force (but only if charged) , Weak Nuclear Force and Strong Nuclear Force. Pions can interact with EM force (but only if charged) , Weak Nuclear Force and Strong Nuclear Force. Neutrinos can only interact with weak nuclear force
Beta plus interaction?
Involves a proton turning into a neutron and electron neutrino and a beta plus particle otherwise a positron
Pion Strangeness?
Pions have no strangeness
Role of mercury vapour compared to coating in flourescent tube?
Mercury vapour emits photons of UV light following ionisation or excitation. Whereas, coating emits photons of visible light following excitation or ionisation after absorbing UV light
Direction of momentum on projection?
Momentum has to be in line with the velocity at a paricular point so will create a tangent where the velocity will be taken and this tangents direction will be direction of momentum
Relationship between voltage and resistance in series with negligible internal resistance?
The ratio of the resistances will be the same as the ratio of the potential differences
