Question

1. a student sets up an experiment using the circuit shown below.

she uses the following bulbs in the circuit, one at a time, and records the readings on the ammeter.
the results obtained are shown in the table below.

circuit	bulb	ammeter reading / a
2	b	0.1
3	c	4.0

(a) describe what happens to the bulbs when placed in the circuit. 1

Explanation:

To determine what happens to the bulbs, we analyze the ammeter readings (current, \( I \)). In a circuit with a fixed voltage (from the battery), current is related to resistance (\( I=\frac{V}{R} \))—higher current means lower resistance, and vice versa. Bulb C has the highest current (4.0 A), so it will be the brightest. Bulb B has the lowest current (0.1 A), so it will be the dimmest. Bulb A (2.0 A) will have brightness between B and C. Thus, the bulbs light up, with Bulb C being the brightest, Bulb B the dimmest, and Bulb A of moderate brightness.

Answer:

The bulbs light up. Bulb C is the brightest, Bulb B is the dimmest, and Bulb A has a moderate brightness (since current: \( C > A > B \), and brightness is related to power \( P = VI \), so higher current means brighter light for the same voltage).