a dentist is using a mirror which being 1.5 cm from a tooth creates a direct image of x 4.5 magnification. what is the radius of curvature of this mirror? give answer in cm.

The momentum of an isolated system is conserved a) only in inelastic collisions. b) only in elastic collisions. c) in both elastic and inelastic collisions

How would you place two electrons on a sphere of radius r so that the electrostatic potential energy is minimized. how would you place three electrons to solve the same problem.

Un jugador de beisbol batea un foul recto en el aire.la pelota deja el bate con una rapidez de 120 km/h. en ausencia de resistencia del aire. ? cual sera la rapidez de la pelota cuando la atrape el catcher