Exams › JEE Main › Physics
A coin rests on a horizontal plate that executes vertical simple harmonic motion with angular frequency ω. If the oscillation amplitude is slowly increased, the coin will first lose contact with the plate
- when the plate is passing through its mean position
- when the amplitude reaches g/ω²
- when the amplitude reaches g/2ω²
- when the plate is at its upper extreme position
Correct answer: when the amplitude reaches g/ω²
Solution
The coin will lose contact with the plate when the upward acceleration of the plate equals the acceleration due to gravity. This occurs when the amplitude of the oscillation reaches g/ω², as this is the point where the maximum upward acceleration of the plate is insufficient to keep the coin pressed against it.
Related JEE Main Physics questions
- A block of mass M is attached to a horizontal spring and oscillates in simple harmonic motion with amplitude A1. When the block crosses the equilibrium position, a smaller mass m is gently placed on it, and thereafter the two move together. The new amplitude is A2. What is the value of the ratio A1/A2?
- An ideal gas is trapped in a vertical cylinder of cross-sectional area A by a frictionless piston of mass M. When the gas volume is V0 and its pressure is P0, the piston is in equilibrium. If the piston is given a small displacement from this position and then let go, and the entire setup is thermally isolated, the piston performs SHM with frequency
- A mass m is connected to a spring with spring constant k, giving it a natural angular frequency ω0. If an external driving force varying as cos(ωt) acts on the system, the oscillator’s displacement will be proportional to
- A particle undergoing simple harmonic motion has kinetic energy K0. The maximum potential energy and the total energy are, respectively,
- A simple pendulum is suspended from the roof of a lift that is initially at rest, and its period is T. The lift then moves upward such that the distance it covers is given by y = t², where y is in metres and t is in seconds. Taking g = 10 m/s², what will be the new time period of the pendulum?
- A damped oscillator’s amplitude falls to 0.9 of its initial value in 5 s. After an additional 10 s, what fraction of the initial amplitude will it have, if the factor is denoted by α?
⚔️ Practice JEE Main Physics free + battle 1v1 →