A 35 kg sledder slides down from the top of a 5.9 m tall hill. The sledder starts with a speed of 2.63 m/s. a) What is the sledder's speed at the bottom of the hill?

b) At the bottom of the hill, the sledder collides with a 50 kg person running at 8.5 m/s directly away from the sledder. You can assume both the sledder and the person are moving due east. The sledder and the person collide and the person falls into the sled. What is the velocity of the sledder and the person after the collision?

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?

Astudent is given an assignment to demonstrate diffraction. he takes a photograph of a straw in a glass of water. the straw appears bent at the water level. which best describes this example? a) this is a good example of diffraction. b) this is an example of dispersion and not diffraction. c) this is an example of refraction and not diffraction. d) this is an example of reflection and not diffraction.

Diamond will scratch quartz. true or false