Answer:
I just took the quiz and got 100% when choosing A.Conservation. Hope this helps:)
Answer:
Either B or D. The answer itself is 2.
Explanation:
The equation for the kinetic energy would be 1/2*mv^2.
When m is doubled, we can plug in 1 and 2 to compare our answers.
Plugging in 1 for mass would give us the answer 1/2*v^2.
Plugging in 2 for mass would give us v^2. This means that the velocity was multiplied by 2, meaning that the answer is it is multiplied by 2.
I am not sure which answer is correct since there seems to be two answer choices with 2 in it, but the answer is either B or D (I will call it ABCD because I do not want to cause confusion by saying 2 multiple times).
The electric potential energy of the charge is equal to the potential at the location of the charge, V, times the charge, q:

The potential is given by the magnitude of the electric field, E, times the distance, d:

So we have

(1)
However, the electric field is equal to the electrical force F divided by the charge q:

Therefore (1) becomes

And if we use the data of the problem, we can calculate the electrical potential energy of the charge:
Energy is calculated as power*time, so give the wattage of 1200 W (equivalent to 1200 Joules/second) and time of 30 seconds, multiplying these gives 36000 J or 36 kJ of electrical energy.
If electrical charge or current is needed: Power = voltage * current, so given the power of 1200 watts and voltage of 120 V, current is 1200 W / 120 V = 10 Amperes. Charge is calculated by multiplying 10 A*30 s = 300 C.
(t) = 2t = 1.22 sec. I believe ...