The human ear canal is about 2.9 cm long and can be regarded as a tube open at one end and closed at the eardrum. What is the fundamental frequency around which we would expect hearing to be most sensitive? Assume the speed of sound in air to be 335 m/s.

Estimate the kinetic energy of the neptune with respect to the sun as the sum of the terms, that due to its daily rotation about its axis, and that due to its yearly revolution about the sun. [assume the neptune is a uniform sphere with mass = 1.0×1026 kg , radius = 2.5×1010 m , rotation period 16.1 h , orbital period 6.01×104 d and is 4.6×109 km from the sun.]