Electromagnetic radiation (light) comprises of waves. More than a century ago, scientists thought that light, like another waves, requisite a medium (known as the ether) to support its transmission. Glass, having a typical mass density of 2650 kg/m^3, as well supports the transmission of light. Determine what would the elastic modulus of glass have to be to support the transmission of light waves at a speed of v = 2.21 x 108 m/s? (For comparison: the real elastic modulus of window glass is around 5 x 10^10 N/m^2.)