The silver coating on the inner bottle prevents heat transfer by radiation, and the vacuum between its double wall prevents heat moving by convection. The thinness of the glass walls stops heat entering or leaving the flask by conduction.
Wavelength is the distance between 2 adjacent points in a wave
we can use the following equation to find the wavelength of a sound wave
wavelength = speed / frequency
frequency is the number of waves passing a point in 1 second
substituting the values in the equation
wavelength = 343 m/s / 686 Hz
wavelength = 0.5 m
wavelength of the wave is 0.5 m
less mass is more mass but less energy in more mass. less mass has more energy
