01
Vector vs scalar. Set a positive direction before every vector calc. Sign every quantity, then combine. 13/15
02
Definitions, word-perfect. Velocity = rate of change of displacement. Not speed. EMF = work done per unit charge by the source. 13/15
03
Diffraction grating: convert lines/mm. 600 lines/mm ⇒ d = 1/(600 × 10³) m. Order n is an integer. 13/15
04
Momentum, signed. Rebound from −8 to +6 = Δv of 14, not 2. Conservation of KE in elastic only. 13/15
05
NOT · EXCEPT · ONLY. Underline every command word. “Best” means most complete. Initial ≠ average ≠ final. 11/15
06
Graphs: area vs gradient. F-e area = work. v-t area = displacement. R is not the gradient of I-V (except ohmic). 10/15
07
Internal resistance. V_terminal = ε − Ir. Doubling external R does not halve current — r is still there. 10/15
08
Nuclear decay. α: A−4, Z−2. β−: Z+1. β+: Z−1. β has a continuous energy spectrum (neutrino). 8/15
09
Newton's 3rd law pair. Same type, different objects. Weight + normal force on a book are not a pair. 5/15
10
SI prefixes & powers of 10. 1 cm² = 10−⁴ m². 1 cm³ = 10−⁶ m³. µ, m, k, M reflexively. 5/15
F = ma only when m is constant; F = dp/dt always
Newton 3rd law pair: same type, different objects
ΔKE = ½m(v² − u²), NOT ½m(v−u)²
Impulse = Ft = Δp (signed)
Hooke's law up to limit of proportionality only
Energy stored in a spring = ½Fe = ½ke²
Stress = F/A; strain = e/L₀; Young modulus = stress/strain
Polarisation only for transverse waves (not sound)
Intensity ∝ amplitude²
Path difference / λ × 360° = phase difference
d sin θ = nλ (grating); λ = ax/D (double slit)
Coherence = constant phase difference + same frequency
R = V/I at operating point, not gradient for non-ohmic
I = nAvq (drift velocity)
Kirchhoff 1: currents balance at a junction
Kirchhoff 2: EMFs = IR drops around a loop
Quarks: proton (uud) = +1; neutron (udd) = 0
β−: n → p + e− + antineutrino; Z+1, A unchanged
β+: p → n + e+ + neutrino; Z−1, A unchanged
SI base units: kg, m, s, A, K, mol, cd