13) Un móvil A parte de una ciudad a las 12 horas, con una velocidad de 40 Km/h. 2 horas después parte otro con una velocidad de 60 Km/h. Averiguar a qué hora se encuentran y a que distancia de la ciudad

How does the image distance (di) of a convex lens compare with the image distance of a concave lens? a. the image distance of the convex lens is positive, and that of the concave lens is negative. b. both are negative for a virtual image. c. both are positive for a virtual image d. the image distance of the convex lens is negative, and that of the concave lens is positive.

J. j. thomson’s experiment disproved the theory that an atom

The mass of a bowling ball is 10 kg and the mass of a ping pong ball is 0.015 kg. if the two objects are 5 meters apart, what is the gravitational force ?