Find the magnitude of the sum of two vectors; A is 5 km , and B is 7 , when the angle btween them is 120

6.24 km

Explanation:

Given

The magnitude of the first vector(say)

the magnitude of the second vector(say)

the angle between them is

The resultant vector magnitude is given by

electrical potential energy =0.072 j

explanation:

electrical potential energy is given by

u= q δv

q= charge=6 c

δv= potential difference and is given by

δv= e d

e= electric field

d= distance=5 mm=0.005 m

δv=2.4 (0.005)=0.012 v

now electric potential energy= u= q δv

u=6 (0.012)

u=0.072 j

the answer is 100. i just did this lesson and got a 100% on it. : )

-fishtank