An old mining tunnel disappears into a hillside. you would like to know how long the tunnel is, but it's too dangerous to go inside. recalling your recent physics class, you decide to try setting up standing-wave resonances inside the tunnel. using your subsonic amplifier and loudspeaker, you find resonances at 5.0 hz and 6.4 hz , and at no frequencies between these. it's rather chilly inside the tunnel, so you estimate the sound speed to be 331 m/s . based on your measurements, how far is it to the end of the tunnel?

An uplifted block of rock between two normal faults

If the spring constant k of a pogo stick is 3500 n m and the weight of the person on the pogo stick is 700 n, how much is the spring in the botom of the pogo stick compressed?

Your starship, the aimless wanderer, lands on the mysterious planet mongo. as chief scientist-engineer, you make the following measurements: a 2.50-kg stone thrown upward from the ground at 14.0 m/s returns to the ground in 5.70 s ; the circumference of mongo at the equator is 2.20×10^5 km ; and there is no appreciable atmosphere on mongo. (a) the starship commander, captain confusion, asks for the following information: what is the mass of mongo? (b) if the aimless wanderer goes into a circular orbit 2.20×10^4 km above the surface of mongo, how many hours will it take the ship to complete one orbit? (c) an unmanned spacecraft is in a circular orbit around the moon, observing the lunar surface from an altitude of 44.0 km . to the dismay of scientists on earth, an electrical fault causes an on-board thruster to fire, decreasing the speed of the spacecraft by 23.0 m/s . if nothing is done to correct its orbit, with what speed (in km/h) will the spacecraft crash into the lunar surface?