F.2 Science ~20 points~

1. B
2. C
3. B

Comment:
1. In the case A, C, D, the voltmeter reading is the same as the battery. Only in the case B, the voltmeter reads the potential difference across one resistor. This P.D. across the resistor is less than the the voltage of the battery

2. Only in C, the circuit is completed. The electric current flows through the light bulb.

3. We use ammeter to measure electric current and it must be in series. Voltmeter is used to measure potential different or voltage.




2010-12-20 01:20:30 補充：
Additional explanation for Question (2):
In case A and B, no current flows through the circuit. Although it is a complete circuit in case D, the current doesn’t have to go through the light bulb.

Q1. B

因為A, C, D係度到電源2端既voltage
你知道in series時 voltage係會分比2個load
B係度到其中1個load既voltage
所以 B係最細

Q2. C

A. X and Y are open circuit 姐係斷晒
B. Y close circuit and X open circuit: 冇complete到circuit
D. Y and X are close circuit: Y段short circuit 冇電到燈泡

Q3. B

度電流係用ammeter 同埋 係in series