Andrés nota que durante el verano tiene serios problemas para poder cerrar su puerta de aluminio durante el día, esto es debido a

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?

Mixing salt in water is an example of physical change

You have 80 g of 60oc water and 80 g or 10oc water. what is the final temperature when the two are mixed? explain.