<span>(a) E = ½ Q²/C, so ..
(b) E(max) = ½Li² (i=current), so .</span>
Answer:
W = 650 [kJ]
Explanation:
The definition of work is denoted by the product of force by the distance traveled by the body, this distance traveled corresponds to the direction of the force.
In this case we have:
d = distance = 2.6[km] = 2600 [m]
F = force = 250 [N]
W = F*d = 250 * 2600 = 650000 [J] or 650 [kJ]
If the resistor is in series with the rest of the circuit then a is the correct answer. The voltage across the resistor in series with another resistor is

where R is the big resistor and r is the small one and V is the total voltage drop across both. This is called a voltage divider