Physics Test 94...

To produce sound waves it is necessary for the source to vibrate

For a transverse wave on a string the string displacement is described by y(x, t) = f(x – at), where 'f ' is a given function and a is a positive constant. Which of the following does NOT necessarily follow from this statement?

A metal wire has these properties: coefficient of linear expansion = 1.5 × 10^–5 (C°)^–1. Young’s modulus = 2.0 × 10¹¹ Pa and density = 9.0 × 10³  kg m^–3. At each end are rigid supports. If the tension in the wire is zero at 20°C, then the speed of a transverse wave in the wire at 8°C will be

A wave is represented by the equation y = 10 sin 2π(100t – 0.02x) + 10 sin 2π(100t+0.02x). The maximum amplitude and loop length are respectively

A recent high precision method of determining g has quoted an error of 6 parts in 10⁹. The increase in height at the surface due to change in g equal to this error is (Take radius of earth as 6400 km)