A Wavelength
B Slit width
C Number of slits
D Ratio d/λ must not exceed 1 for sin θ
Explanation: The maximum order n is limited by d sin θ = nλ, where sin θ ≤ 1, so n ≤ d/λ.
A I₀/2
B I₀/4
C I₀
D I₀/√2
Explanation: By Malus\'s law: I = I₀ cos²θ = I₀ cos²45° = I₀ × (1/√2)² = I₀/2
A Maximum
B Minimum
C Zero
D Infinite
Explanation: Kirchhoff\'s junction rule states ΣI = 0 at any junction, based on conservation of charge.
A Positive
B Negative
C Zero
D Equal to EMF
Explanation: Kirchhoff\'s loop rule states ΣV = 0 around any closed loop, based on conservation of energy.
A Maximum
B Minimum
C Equal
D Zero
Explanation: Wheatstone bridge is balanced when P/Q = R/S, making the galvanometer reading zero.
Explanation: E = hf = hc/λ, where h is Planck\'s constant and f is the frequency of the photon.
A 0.123 nm
B 1.23 nm
C 0.012 nm
D 12.3 nm
Explanation: λ = h/√(2meV) = 1.227/√V nm. For V = 100, λ = 1.227/10 = 0.1227 nm ≈ 0.123 nm
A Longer
B Shorter
C Same
D Zero
Explanation: Length contraction: L = L₀√(1-v²/c²). Moving objects appear shorter in the direction of motion.
A m₀
B m₀/√(1-v²/c²)
C m₀√(1-v²/c²)
D m₀(1-v²/c²)
Explanation: Relativistic mass: m = m₀/√(1-v²/c²). Mass increases with velocity.
A Faster
B Slower
C Same speed
D Stops
Explanation: Time dilation: Δt = Δt₀/√(1-v²/c²). Moving clocks run slower than stationary ones.
A E = mv²
B E = mc²
C E = hν
D E = p²/2m
Explanation: Einstein\'s mass-energy equivalence: E = mc², where c is the speed of light.
A Intensity of light
B Frequency of light
C Time of exposure
D Number of photons
Explanation: KE_max = hf - φ, so maximum kinetic energy depends on the frequency of incident light, not its intensity.
A 13.6 eV
B 3.4 eV
C 0.85 eV
D 1.51 eV
Explanation: The energy needed to remove an electron from ground state (n=1) is 13.6 eV.
A nh
B n²h
C nh/2π
D n/2πh
Explanation: Bohr\'s quantization condition: L = nh/2π = nℏ, where ℏ = h/2π.
A Electrons
B Helium nuclei
C Protons
D Neutrons
Explanation: Alpha particles are helium nuclei (⁴He²⁺) with mass number 4 and charge +2e.
A Electron
B Proton
C Alpha particle
D Gamma ray
Explanation: In beta minus decay, a neutron converts to a proton, emitting an electron and antineutrino.
A Charged particles
B High energy photons
C Electrons
D Neutrons
Explanation: Gamma rays are high energy electromagnetic photons emitted during nuclear transitions.
A λ = t½/ln2
B λ = ln2/t½
C λ = t½ × ln2
D λ = 1/t½
Explanation: λ = ln2/t½. The decay constant and half-life are inversely related.
A Becquerel
B Curie
C Rutherford
D All of the above
Explanation: Activity can be measured in Becquerel (SI), Curie, or Rutherford units. 1 Ci = 3.7 × 10^10 Bq.
A p-side to negative, n-side to positive
B p-side to positive, n-side to negative
C Both sides to positive
D Both sides to negative
Explanation: Forward bias: p-side connected to positive terminal, n-side to negative, reducing the barrier potential.