The phenomenon of persistence of hearing is used in MCQ with Answer and Explanation
Question
Report Error
Discuss this Question (0)
Practice More Physics Questions
Question #1
Report Error
A positively charged particle is projected precisely parallel to a uniform magnetic field. The trajectory of the particle will be a:
Correct Answer: Option B
Explanation:
The magnetic Lorentz force on a moving charge is F = q(v x B) = qvBsin(theta). If the particle moves completely parallel to the magnetic field, the angle theta is 0 degrees. Since sin(0) = 0, the magnetic force is absolutely zero. Experiencing no transverse force, the particle continues moving in a perfect straight line.
The magnetic Lorentz force on a moving charge is F = q(v x B) = qvBsin(theta). If the particle moves completely parallel to the magnetic field, the angle theta is 0 degrees. Since sin(0) = 0, the magnetic force is absolutely zero. Experiencing no transverse force, the particle continues moving in a perfect straight line.
Question #2
Report Error
In a series LCR circuit at resonance, the impedance is:
Correct Answer: Option A
Explanation:
At resonance frequency ω₀ = 1/√(LC), inductive reactance X_L = ωL equals capacitive reactance X_C = 1/(ωC), so they cancel. Impedance Z = √[R² + (X_L - X_C)²] = R, which is minimum (since R is the only remaining component). Current is maximum at resonance. Memory tip: 'LCR resonance: Z_min = R, I_max, purely resistive'. This AC circuit concept is frequently tested in competitive exams. Always distinguish series resonance (Z min) from parallel resonance (Z max) behavior.
At resonance frequency ω₀ = 1/√(LC), inductive reactance X_L = ωL equals capacitive reactance X_C = 1/(ωC), so they cancel. Impedance Z = √[R² + (X_L - X_C)²] = R, which is minimum (since R is the only remaining component). Current is maximum at resonance. Memory tip: 'LCR resonance: Z_min = R, I_max, purely resistive'. This AC circuit concept is frequently tested in competitive exams. Always distinguish series resonance (Z min) from parallel resonance (Z max) behavior.
Question #3
Report Error
A man of mass 60 kg stands on a weighing machine in a lift accelerating upward at 2 m/s². Reading in kg wt (g=10) is
No comments yet. Be the first to start the discussion!