What is a controlled experiment?
a. two variables are changed at a time
b. all variables are kept constant
c. none of the variables are changed
d. one variable is changed at a time

What must be the same for any two resistors that are connected in series ? a. the potntial diffrence across each b. the rate at which charge moves through each c. the rate at which energy is used by each d. the resistance to the flow of charge of each

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

What are atoms of the same element with varying number of neutrons