Hannah puts 25,000 joules of work into the machine. The machine, in turn, puts out 21,000 joules of work. What is the efficiency of the machine?

Find the momentum for a 2.6-kg brick parachuting straight downward at a constant speed of 8.4 m/s .

The chemical effect of the endocrine system is longer lasting than the chemical effect of the nervous system. select the best answer from the choices provided t f

Abird flies directly overhead from where you stand at an altitude of 300.0 m and at a speed horizontal to the ground of 20.0 m/s. the bird has a mass of 2.0 kg. the radius vector to the bird makes an angle \thetaθ with respect to the ground. the radius vector to the bird and its momentum vector lie in the xyxy-plane. what is the bird’s angular momentum about the point where you are standing?