The following table lists the speed of sound in various materials. use this table to answer the question.

substance speed (m/s)
glass 5,200
aluminum 5,100
iron 4,500
copper 3,500
salt water 1,530
fresh water 1,500
mercury 1,400
hydrogen at 0°c 1,284
ethyl alcohol 1,125
helium at 0°c 965
air at 100°c 387
air at 0°c 331
oxygen at 0°c 316
sound will travel the slowest in

air
glass
aluminum
water

In a wind tunnel the speed changes as the cross sectional area of the tunnel changes. if the speed in a 6' x 6' square test section is 100 mph, what was the speed upstream of the test section where the tunnel measured 20' x 20'? use conservation of mass and assume incompressible flow. conservation of mass requires that as the flow moves through a path or a duct the product of the density, velocity and cross sectional area must remain constant; i.e., that ova-constant. a model is being tested in a wind tunnel at a speed of 100 mph if the flow in the test section is at sea level standard conditions, what is the pressure at the model's stagnation point? (a) the tunnel speed is being measured by a pitot-static tube connected to a u- tube manometer. what is the reading on that manometer in inches of water? (b) at one point on the model a pressure of 2058 psf is measured. what is the local airspeed at that point?

An isotope undergoes radioactive decay by emitting radiation that has a –1 charge. what other characteristic does the radiation have?

Calculate the numbers of photons having a wavelength of 10.0 mm required to produce 1.0 kj of energycalculate the numbers of photons having a wavelength of 10.0 mm required to produce 1.0 kj of energy