Very large forces are produced in joints when a person jumps from some height to the ground. Calculate the force produced if an 79.0–kg person jumps from a 0.510–m-high ledge and lands stiffly, compressing joint material 1.30 cm as a result. (Be certain to include the weight of the person.) 3.04*10^4J Incorrect. Tries 1/7 Previous Tries In practice the knees bend almost involuntarily to help extend the distance over which you stop. Calculate the force produced if the stopping distance is 0.345 m. 1.92×103 J You are correct. Find the ratio of the force in part (a) with the weight of the person. Tries 0/7 Find the ratio of the force in part (b) with the weight of the person.

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?

Modern physics a photon emitted from an excited hydrogen atom has an energy of 3.02 electron volts. which electron energy-level transition would produce this photon? a. n=1 to n=6 b. n=2 to n=6 c. n=6 to n=1 d. n=6 to n=2 i chose b but the correct answer is d can someone tell me why? and what's the difference?

Explain the comparisons between nature and packingtown that appears on pages 81 and 82 answer