Total resistance=R1+ R2= 6Ω
Voltage=12v
Current =

Current= 2A
In a series circuit, equal current passes through every resistance.
Answer is option A
Answer:
<em> 3980.89 ohms</em>
Explanation:
The capacitive reactance is expressed as;

f is the frequency
C is the capacitance of the capacitor
Given
f = 60H
C = C1+C2 (parallel connection)
C = 15μF + 25μF
C = 40μF
C = 
Substitute into the formula:

<em>Hence the total capacitive reactance is 3980.89 ohms</em>
Answer:
Same direction: t=234s; d=6.175Km
Opposite direction: t=27.53s; d=0.73Km
Explanation:
If the automobile and the train are traveling in the same direction, then the automobile speed relative to the train will be
(<em>the train must see the car advancing at a lower speed</em>), where
is the speed of the automobile and
the speed of the train.
So we have
.
So the train (<em>anyone in fact</em>) will watch the automobile trying to cover the lenght of the train L at that relative speed. The time required to do this will be:

And in that time the car would have traveled (<em>relative to the ground</em>):

If they are traveling in opposite directions, <u>we have to do all the same</u> but using
(<em>the train must see the car advancing at a faster speed</em>), so repeating the process:



There are missing data in the text of the problem (found them on internet):
- speed of the car at the top of the hill:

- radius of the hill:

Solution:
(a) The car is moving by circular motion. There are two forces acting on the car: the weight of the car

(downwards) and the normal force N exerted by the road (upwards). The resultant of these two forces is equal to the centripetal force,

, so we can write:

(1)
By rearranging the equation and substituting the numbers, we find N:

(b) The problem is exactly identical to step (a), but this time we have to use the mass of the driver instead of the mass of the car. Therefore, we find:

(c) To find the car speed at which the normal force is zero, we can just require N=0 in eq.(1). and the equation becomes:

from which we find