một viên đá được cột vào đầu sợi dây dài 0,5m rồi quay sợi dây cho viên đá chuyển động tròn đều sao cho mỗi giây nó thực hiện được 2 vòng, gia tốc của viên đá là

An electron and a proton have the same kinetic energy upon entering a region of constant magnetic field and their velocity vectors are perpendicular to the magnetic field. suppose the magnetic field is strong enough to allow the particles to circle in the field. note: you'll need to look up the masses for an electron and proton. 1) what is the ratio of the radii of their circular paths rp/re?

You are about to open a container of soy milk but notice that there are instructions to “shake well before serving.” the soy milk is most likely a

Which changes would result in a decrease in the gravitational force btween two objects? check all that apply