Two trains leave the station at the same time, one heading east and the other west. the eastbound train travels at 80 miles per hour. the westbound train travels at 90 miles per hour. how long will it take for the two trains to be 306 miles apart?

Using a wheel and axle, a farmer is trying to lift a bucket of water from the bottom of a well. the larger wheel has a radius of 40 cm compared to the axle that has a radius of 10 cm. if a bucket of water is 50 n, then how much effort is required to raise it? 12.5 n 200 n 2 n 500 n

Atwo-stage air compressor operates at steady state, compression 10m^3/min of air from 100 kpa and 300k to 1200 kpa. an intercooler between the two stages cools the air to 300k at a constant pressure of 350 kpa. the compression processes are isentropic. a) calculate the power required to run the compressor, in kw b) compare the result to the power required for isentropic compression from the same inlet state to the same final pressure.

If a substance is in the gas phase, which of qualities of the gas will stay constant? a: volume b: mass c: shape d: position of particles