(magnetism,$4.5 \mathrm{V}$,$3.0 \mathrm{V}$, gravitational attraction, potential difference, potential, higher, lower, $0 \mathrm{V}$) 

Water in the waterfall flows from a higher level to the lower level because of .

The difference between the electrostatic potential of the positive end the negative end of an electric cell is the _____ of the cell. (magnetism, $4.5 \mathrm{V}$, $3.0 \mathrm{V}$, gravitational attraction, potential difference, potential, higher, lower,$0 \mathrm{V}$) 

An electric current flowing in a wire creates _____ around the wire. (magnetism,$4.5 \mathrm{V}$, $3.0 \mathrm{V}$, gravitational attraction, potential difference, potential, higher, lower, $0 \mathrm{V}$) 

Electric cells having $2 \mathrm{V}$ potential difference, each have been connected in the form of a battery. What will be the total potential difference of the battery in this case?
 

Electric cells having $2 \mathrm{V}$ potential difference, each have been connected in the form of a battery. What will be the total potential difference of the battery in this case?