For a simple harmonic oscillator, the velocity vvv as a function of displacement xxx and amplitude x0x_0x0 is given by the equation:
v=ωx02−x2 v = \omega \sqrt{x_0^2 - x^2} v=ωx02−x2where ω\omegaω is the angular frequency. Show that this equation is homogeneous by reducing both sides to S.I. base units.
A glass U-tube is partially filled with oil. One end of the U-tube is connected to a gas supply of constant pressure and the other end is open to the atmosphere. The displacement of the oil from its equilibrium position is xxx. The density ρ\rhoρ of the oil is 800 kg m−3800\text{ kg m}^{-3}800 kg m−3.
The pressure from the gas supply raises the oil on one side of the U-tube. The vertical distance between the two levels of oil in the two vertical sections of the U-tube is 15.0 cm15.0\text{ cm}15.0 cm (x=7.5 cmx = 7.5\text{ cm}x=7.5 cm). Δp\Delta pΔp is the difference between the gas pressure and atmospheric pressure. Calculate Δp\Delta pΔp.
When the gas supply is disconnected, the oil levels in the U-tube oscillate with simple harmonic motion. The acceleration aaa of the oil level is given by the equation:
a=−2ρgAmx a = -\frac{2\rho g A}{m} x a=−m2ρgAxwhere mmm is the mass of the oil in the U-tube, AAA is the internal cross-sectional area of the U-tube, ρ\rhoρ is the density of the oil, ggg is the acceleration of free fall (9.81 m s−29.81\text{ m s}^{-2}9.81 m s−2), and xxx is the displacement.
For this U-tube, A=1.2×10−4 m2A = 1.2 \times 10^{-4}\text{ m}^2A=1.2×10−4 m2 and m=0.075 kgm = 0.075\text{ kg}m=0.075 kg. Show that the period TTT of the oscillations is approximately 1.3 s1.3\text{ s}1.3 s.