Can you explain the answer of this question below:The decrease of resistance in parallel combination is due to:A:The decrease in effective area of the cross-section.B:The increase in effective area of the cross-section.C:The decrease in effective length.D:None of the aboveThe answer is b.

Question

Answer

Resistance (R)depends on the resistivity of the nuteial (pl. length of the oats' (Li and cross sectional area (A) of the material following the equation:

R = p* L/A

When hooking resistors in parallel, you are increasingthecross sectional area of the resistance path. If you like to use the water hose analogy, you are draining the tub (battery - power source)with two hoses (resistors)instead of one. It makes the tub move water (current) Faster because you have more paths (bigger cross sectional area) for the water to flow.

If you look at the original equation above you will notice that replacing A with 2A (two of the same resistors in parade) you will cut the resistance in half.

That's the theory. In practice. to find the resistance you would Ix/mayjust add the reciprocal ol the usevidual resistors to get the reciprocal of the total resistance

1/R -total = 1/RI + 1/R2 + 1/R3 + ....

for however many resistors you have in parallel. For example.

If you have only 2 resistors in parallel. a 50 ohm in parallel with a 100 ohm resistor then...

1/R - total = 1 /50 ohm + 1/100 ohm = 2/100 ohm + 1/100 ohm

= 3/100 ohm

so,

R - total = 103/3 = 33.3 ohm (most peocre forget die step)

A good rule to remember is that you total resistance is less than the smallest resistor when they are connected in parallel.

Answer

Explanation:
When two or more resistors are connected in parallel, the total resistance of the circuit decreases. This is due to the increase in effective area of the cross-section.

Effective area of the cross-section:
The effective area of the cross-section is the area through which the current flows. In a wire, the effective area of the cross-section is proportional to the square of the radius of the wire. When two or more resistors are connected in parallel, the total effective area of the cross-section increases.

Explanation using Ohm's law:
Ohm's law states that the current flowing through a conductor is directly proportional to the voltage applied across it and inversely proportional to the resistance of the conductor. Therefore, if the resistance of a conductor decreases, the current flowing through it increases.

When two or more resistors are connected in parallel, the voltage across each resistor is the same. However, the total current flowing through the circuit is divided among the resistors. Therefore, each resistor experiences a smaller current than if it were connected alone.

Since the current flowing through each resistor is smaller, the effective resistance of each resistor is also smaller. Therefore, the total effective resistance of the circuit is smaller than the resistance of any of the individual resistors.

Conclusion:
In conclusion, the decrease of resistance in parallel combination is due to the increase in effective area of the cross-section.

Answer

This is because resistance of a conductor is inversely proportional to its area of cross section.

Answer

Resistance is inversely proportional to the area of cross section.. hence, increase in area leads to decrease in the resistance.

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