A 1.097 × 10^7 m⁻¹
B 6.674 × 10⁻¹¹ N·m²/kg²
C 8.987 × 10^9 N·m²/C²
D 9.109 × 10⁻³¹ kg
Explanation: R = 1.097 × 10^7 m⁻¹ is the Rydberg constant used in the hydrogen spectral series formula.
A Lyman series line
B Balmer series line
C Paschen series line
D Brackett series line
Explanation: Transitions to n=2 produce the Balmer series (visible light region).
A 13.6 eV
B 3.4 eV
C 10.2 eV
D 6.8 eV
Explanation: ΔE = 13.6(1 - 1/4) = 13.6 × 3/4 = 10.2 eV
A Parallel to the magnetic field
B Perpendicular to the magnetic field
C At 45° to the field
D At 60° to the field
Explanation: When the plane is parallel to the field, the area vector is perpendicular, giving maximum torque τ = M × B.
A Frequency of AC voltage
B Magnetic field and radius of dees
C Only the mass of particle
D Only the charge of particle
Explanation: KE_max = q²B²R²/(2m), depending on magnetic field B and radius R of the dees.
A Steady current
B Change in current
C Voltage
D Resistance
Explanation: Self-inductance produces a back EMF that opposes any change in current (Lenz\'s law applied to self-induction).
Explanation: Energy stored in inductor = ½LI², analogous to energy stored in capacitor = ½CV².
Explanation: Z = √(R² + XL²) = √(9 + 16) = √25 = 5 Ω
Explanation: tan φ = XC/R = 10/10 = 1 → φ = tan⁻¹(1) = 45°. Current leads voltage.
Explanation: At resonance, Z = R (minimum), so power factor cos φ = R/Z = 1. Circuit behaves as purely resistive.
Explanation: Number of neutrons = Mass number - Atomic number = 235 - 92 = 143
A Total energy released
B Mass of products
C Kinetic energy of products
D Binding energy of products
Explanation: Q-value = (mass of reactants - mass of products)c² = total energy released in the nuclear reaction.
A Atoms move faster
B Coulomb barrier must be overcome
C Gravity increases
D Neutrons are released
Explanation: Nuclei must have enough kinetic energy to overcome the Coulomb repulsion between positively charged nuclei.
A Parallel
B Perpendicular to each other and to propagation
C At 45° to each other
D In the same direction
Explanation: In EM waves, E and B fields are perpendicular to each other and both are perpendicular to the direction of wave propagation.
A 3 × 10^8 m/s
B 3 × 10^6 m/s
C 3 × 10^10 m/s
D 3 × 10^5 m/s
Explanation: All electromagnetic waves travel at c = 3 × 10^8 m/s in vacuum.
A Faraday
B Maxwell
C Ampere
D Gauss
Explanation: Maxwell introduced the concept of displacement current to make Ampere\'s law consistent for time-varying fields.
A Amplitude only
B Frequency only
C Square of amplitude
D Wavelength
Explanation: Energy density u = ε₀E² = ε₀E₀² sin²(ωt-kx), proportional to the square of the amplitude.
A Energy density
B Energy flux density (power per unit area)
C Magnetic flux
D Electric flux
Explanation: Poynting vector S = E × B/μ₀ represents the directional energy flux (power per unit area) of the EM wave.
A Are accelerated
B Hit a metal target
C Are deflected by magnetic field
D Combine with protons
Explanation: X-rays are produced when high-speed electrons are suddenly decelerated upon striking a metal target.
A 1.24 eV
B 2.48 eV
C 3.72 eV
D 0.62 eV
Explanation: φ = hc/λ₀ = 12400/5000 = 2.48 eV