How does a windmill work

a hammer falls off a roof and strikes the ground with a certain kinetic energy. If it fell from a roof twice as tall, how ouwld its kinetic energy compare? Explain.

A man on a beach measures 2 seconds and 5 meters between two crests. what is the wave speed?

Do winds and currents flow faster at the equator than at the poles, or more slowly? Think about what you know regarding the shape and rotation of the Earth, the directions of currents, and convection. Make inferences from what you know.

The apparent backward movement of a planet is called A. Kepler's first law of motion. B. heliocentric motion. C. eccentricity. D. retrograde motion.

A bucket of water of mass 20kg is pulled at a constant velocity up to a platform 40 meters above the ground. this takes 10 minutes, during which time 5kg of water drips out at a steady rate through a hole in the bottom.

A basketball player drops a 0.60-kg basketball vertically so that it is traveling at 6.3 m/s when it reaches the floor. The ball rebounds upward at a speed of 5.3 m/s.

Describe how humans' actions and natural processes have modified coastal regions in Louisiana and other locations

Visualize five horizontal sedimentary strata exposed in a cliff or canyon wall identified by consecutive numbers, 1 being the lowest bed and 5 being the highest. Which of the following statements concerning the strata are true? a.

The characteristics that follow are characteristics of two of Galileo's surviving double-convex lenses. The numbers given are magnitudes only; you must supply the correct signs. L 1: front radius 950 mm, rear radius 2700 mm, refractive index 1.

Which car has the most kinetic energy? A car of mass 1500 kg with speed 5 m/s or A car of mass 1300 kg with speed 3 m/s or a car of mass 1200 kg with speed 2 m/s or a car mass 1400 kg with speed 4 m/s