Calculate the elastic potential energy stored in a spring if it has a force constant of 150 N/m. the spring is extended to a length of 0.30m

Alightning strike consists of charge moving from a cloud to the ground . in one particular case, the electrons in a lightning strike are confined to travel within a radius of 1.5 m and to move at a speed of 5.0 x 10 m/s. if the density of electrons in the strike is 10'15 electrons/m what current is carried by the lightning ?

Will a heavier bowling ball hit pins better than a lighter bsll

Anybody wanna ? (picture included? )