The \"air pressure\" analogy - An electric circuit is like air flowing through a

Question

The "air pressure" analogy - An electric circuit is like air flowing through a tube. The air is like movable charge, the flow of the air is like current, and the pressure in the air is like voltage.

The "loop of rope" analogy - An electric circuit is like a loop of rope going through a number of metal rings (or through pulleys or people's hands). The rope is like movable charge, its movement is like current, the rings (or pulleys or hands) are like bulbs, and tension in the rope is like voltage.

1. If the two circuits shown at the left above (marked (a)) are set up with identical batteries and identical bulbs, the bulb on the left will be significantly brighter. Use the two analogies to try to explain this result.


2. If the circuit shown second from the right (marked (b)) is set up with batteries and bulbs identical to the ones in A, the bulbs in this circuit will have equal brightness but be much less bright than the bulb in the circuit at the right above. Use the two analogies to try to explain this result.


3. What, if anything, would the air pressure analogy and loop of rope analogies suggest about the brightness of the bulbs at the right above (marked (c)) compared to each other and to a single-bulb circuit?

Explanation / Answer

1. Left circuit have double battery so double pressure in pipe so flow of air is more so brightness of left bulb is more compared to right.

2. in figure B rope is supported by 2 supports so force/tention is devided by 2 between 2 supports hence voltage is also devided by 2 for eace bulb.  so 2 bulb will have equal brightness but less than circuit (c)

3. 2 bulbs can be like 2 flow pipe so overall flow rate will be double but flow in each pipe will be due to pressure equal to one battery. In a single bulb circuit current will be half of total current in figure (c) but equal to each individual resistor.

Related Questions

Navigate

• Browse (All)
• Browse T
• Subjects

Integrity-first tutoring: explanations and feedback only — we do not complete graded work. Learn more.