The hollow tube is pivoted about a horizontal axis through point O and is made to rotate in the vertical plane with a constant counterclockwise angular velocity ⋅ θ = 3 rad / sec θ·=3 rad/sec. If a 0.2‐lb particle is sliding in the tube toward O with a velocity of 6 ft/sec relative to the tube when the position θ = 30° is passed, calculate the magnitude N of the normal force exerted by the wall of the tube on the particle at this instant.

Aloaded platform of total mass 500 kg is supported by a dashpot and by a set of springs of effective stiffness 72 kn/m. it is observed that when the platform is depressed through a distance x = 12.5 cm below its equilibrium position and then released without any initial velocity; it reaches its equilibrium position in the shortest possible time without overshoot. find the position and velocity of the loaded platform 0.10 sec. after its release. if a further load of 400 kg is added to the platform, find, i) the frequency of damped vibrations, and i) the amplitude of vibration after 2 complete oscillations, given that the initial amplitude is 15 cm.

Manometers are good examples of measuring instruments, nowadays they are not as common as before. a)-capacitive probe gauges b)-gravitational gauges deformation ) gauges d)-digital gauges

Plan an experiment to measure the surface tension of a liquid similar to water. if necessary, review the ncfmf video surface tension for ideas. which method would be most suitable for use in an undergraduate laboratory? what experimental precision could be expected?