Waves, Sound and Oscillations MCQs for MDCAT

Correct answer: C. f = λ

The wave equation relates frequency, speed and wavelength as f = v/λ, so frequency equals speed divided by wavelength.

Correct answer: C. a = - x 10

For SHM, acceleration relates to displacement by a = -ω²x, where ω = 2π/T; with T = 10 s, ω = 2π/10, giving a = -(2π/10)²x.

Correct answer: A. 1 − x 2

The ratio of kinetic energy to total energy in SHM at displacement x is given by 1 − (x²/xo²), which decreases as displacement increases toward the amplitude.

Correct answer: A. f max , λ min

When electrons lose their entire kinetic energy in a single collision, the resulting X-ray photon has the maximum possible frequency and, correspondingly, the minimum possible wavelength.

Correct answer: D. Loudness

Increasing the amplitude of a wave refers to increasing the magnitude or height of the wave. The amplitude is directly related to the loudness or volume of the sound. When the amplitude of a sound wave increases, the sound becomes louder.

Correct answer: B. Double

The relationship between the frequency and the mass of an object undergoing simple harmonic motion can be expressed as: f = 1 / √M When the mass is reduced to one fourth (M/4), the frequency can be calculated as: f ' = f √(M/4) f ' = f (√M) / 2 Therefore, the frequency is doubled when the mass is reduced to one fourth.

Correct answer: A. Longer

In Compton effect, the wavelength of the scattered photon is higher than that of the incident photon.

Correct answer: A. 6.6 X 10-10 m

Step 1: Calculate the momentum (p)p=mv=10-24kgm/sStep 2: Calculate the de Broglie wavelengthNow, substitute p into the de Broglie wavelength formula:λ=hp=6.626×10−34 Js10−24 kg m/s=6.6x10-10m

Correct answer: B. 4T

The frequency of a stretched string is given by the formula f = (1/2L)√(T/μ), where T is the tension, L is the length of the string, and μ is the linear mass density. To double the frequency (2f), we set up the equation: 2f = (1/2L)√(T'/μ), where T' is the new tension. By squaring both sides and solving for T', we find that (2f)² = (1/2L)²(T'/μ). This leads to the conclusion that T' = 4T. Therefore, to double the frequency, the tension must be quadrupled. The other options are incorrect because:2T: Simply doubling the tension does not suffice to double the frequency, as frequency increases with the square root of tension.8T: Increasing to 8T would increase the frequency by a factor of 2.83, which is more than double.16T: Quadrupling the tension results in a frequency increase of 4 times, not just double.

Correct answer: A. Half the energy of a photon in beam B

Since energy is inversely proportional to wavelength, doubling the wavelength cuts the energy in half. So a photon in beam A has half the energy of a photon in beam B.

Correct answer: C. Wavelength, frequency and speed of wave

A wave is typically characterized by the following physical parameters:1. Wavelength (λ): The distance between two consecutive points on the wave that are in phase with each other.2. Frequency (f): The number of oscillations or cycles of the wave per second.3. Speed of wave (v): The distance traveled by the wave per unit time.These three parameters are related by the wave equation:v = λf

Correct answer: A. Longitudinal waves

Longitudinal waves are waves in which the particles of the medium vibrate back and forth along the direction of propagation of the wave. This means that the particles compress and expand in the same direction as the wave is traveling. Examples of longitudinal waves include sound waves in a gas or liquid, and seismic P-waves in the Earth.