Which pair of ratios form a proportion? A. 2 : 3 and 3 : 4 B. 8 : 12 and 16 : 20 C. 4 : 7 and 12 : 21 D. 9 : 15 and 10 : 16

A

Step-by-step explanation:

C 4:7 and 12:21

Step-by-step explanation:

4×3 => 12

7×3 => 21

step-by-step explanation:

we can use this expression to calculate the energy gain as a particle moves with a field or the energy loss as it moves against it. (note that it is also used to define the electron-volt, a unit of energy equal to that gained by an electron as it falls through a pd of 1 v, i.e. w = 1 ev = 1.6 10-19 c 1 v = 1.6 10-19j).in fact this expression is really nothing more than the statement that potential is the potential energy per unit charge. in this case, v= w/qis simply stating that the change in potential energy(or work done) per unit charge is equal to the change in potential (or potential difference), v.student questions: uniform electric fields2electron beamcathode+5 kvanode0 v