What is the density of 15kg block of wood wuth a volume of 1.5 cubic meters

Can somebody explain to me how newton's 3rd law relates to momentum? ~ap physics 1

What happens when you slowly pulled the carboard?

Four point charges each having charge q are located at the corners of a square having sides of length a. find symbolic expressions for the following. (a) the total electric potential at the center of the square due to the four charges (use any variable or symbol stated above along with the following as necessary: ke.) vtotal= (b) the work required to bring a fifth charge p from infinity to the center of the square (use any variable or symbol stated above along with the following as necessary: w=