When a wave travelling in a medium is reflected from the boundary of a denser medium,which of the following will not change?

The displacement $y$ (in $cm$) in case of a simple harmonic wave is given by $y=\frac{10}{\pi} \sin \left(2000 \pi t-\frac{\pi x}{17}\right)$. The period and maximum velocity of the particles in the medium will respectively be

An observer on a sea-coast counts $45$ waves in one minute. If the wavelength of the waves is $7 \ m$,then the velocity of the waves will be (in $m/s$)

The equation of wave motion is $Y = 5 \sin (10 \pi t - 0.02 \pi x + \pi / 3)$ where $x$ is in $m$ and $t$ is in $s$. The velocity of the wave is (in $m/s$)

The figure shows the shape of a part of a long string in which transverse waves are produced by attaching one end of the string to a tuning fork of frequency $250 \ Hz$. What is the velocity of the waves in $ms^{-1}$?

The equation of a transverse wave travelling along a string is $y(x, t) = 4.0 \sin(20 \times 10^{-3} x + 600 t) \ mm$,where $x$ is in $mm$ and $t$ is in seconds. The velocity of the wave is: