Oscillations and Waves — Prelims Questions

A particle executes SHM with an amplitude of $4,\text{cm}$ and a period of $2,\text{s}$. The velocity of the particle when its displacement is $2,\text{cm}$ is:

A sound wave travels from air into water. Which of the following quantities remains unchanged?

A pipe open at both ends has a fundamental frequency of $300,\text{Hz}$. If one end of the pipe is closed, what will be its new fundamental frequency?

Two waves are represented by $y_1 = A sin(omega t + kx)$ and $y_2 = A cos(omega t + kx)$. The phase difference between them is:

A simple pendulum has a time period $T$. If its length is increased by $21$, what will be the new time period?

A source of sound is moving towards a stationary observer with a speed of $v_s = v/10$, where $v$ is the speed of sound. The ratio of the apparent frequency to the original frequency is: