Three resistors of 3.3 kΩ, 4.7 kΩ and 3.9 kΩ are connected in series across a 12 V battery
a. What is the equivalent resistance?
b. What is the current through the resistors?
c. Find the total potential difference across the three resistors.

Explanation:

A.) equivalent resistance

Equivalent resistance ( Rt ) in a series connection is sum of all resistance.

Rt = 3300 + 4700 + 3900

= 11900 ohms

= 11.9 k ohm

B.) current is constant across the whole circuit if it is in series .

current = potential difference ÷ total resistance

current = 12 / 11900 = 0.00100 Amphere

= 0.1 mA

C. potential difference ( v ) across the circuit =

current( i ) × resistance ( Rt )

=》v = 0.1 × 0.001 × 11900 = 12 volts

12000j is work done

when jerome paddle in flowing river towards east the net speed of jerome will increase

so the net speed of jerome will be given as

now the speed of paul will be same as it is given as he is running on the ground

so

so here we can say since the speed of jerome is more so he will win the race

now as we know the distance so the time difference is given as

so jerome will reach first and the time difference will be 203.55 s or 3.4 min