If the form of a sound wave traveling through air is s(x, t) = (7.0 nm) cos(kx + (3000 rad/s)t + φ), how much time does any given air molecule along the path take to move between displacements s = +2.1 nm and s = -2.1 nm?

Rohit is trying to tune an instrument

What causes the formation of ocean currents?

You throw a small rock straight up from the edge of a highway bridge that crosses a river. the rock passes you on its way down, 7.00 s after it was thrown. what is the speed of the rock just before it reaches the water 28.0 m below the point where the rock left your hand? ignore air resistance.